Sen. William "Mo" Cowan (D-Mass.) is getting ready to leave Washington in the coming days. He'll be replaced by Rep. Edward J. Markey (D-Mass.), who won the Massachusetts special election Tuesday night to replace former Sen. John F. Kerry (D-Mass.).

In Wednesday's Washington Post, we write about Cowan's service as a six-month Senate seatwarmer and how, despite all the fun, he's not eager to stick around.

Sen. William "Mo" Cowan (D-Mass.). (AP)

Cowan recently agreed to discuss his brief tenure and his unique opportunity to see the Senate in action up close. We spoke from his office, used by Kerry before he stepped down to serve as secretary of state.

A transcript of the interview -- edited for length and clarity -- appears below:

Ed O'Keefe: So where were you the day that Gov. Patrick called to tell you about serving as senator?

Cowan: You know what, I was actually home - I took the day off that day. I can’t remember if the kids had something, it was something related to my kids, school or something. But I was home, and he called, and with his team of advisers, and told me that he was going to appoint me. And asked me if I was willing to serve. It’s hard to say no to Governor Patrick.

What was your first thought when they asked?

Cowan: There goes my anonymity. There goes my privacy, which was brought in sharp relief the next day after the press conference when my wife returned home and was met by television trucks outside our house and reporters ringing the doorbell. Such is the way of life, I suppose.

Where do you stay when you’re down here? You can’t really get a six-month lease on a place, can you?

Cowan: No, I never even thought about it. I actually have friends and family in the area and I’m staying with some relatives just down the street and across the line in Silver Spring. It’s really convenient.

We’re intrigued by the fact that there are so few people who get to come here under these circumstances. But we wanted to get your perspective, because usually folks have to spend millions of dollars and years of their life getting here. Clearly you didn’t need to do that.

Cowan: Yeah, listen, I have great respect for those who come to the Senate through the traditional mechanism or means. It is a hard slog, it’s probably harder than it’s ever been, that’s the impression I get both as an observer and listening to some of my colleagues. But I can understand the desire to be here and the willingness to put in that effort. It is an honor and privilege to serve. Certainly that is the case for me.

I joke that I’ve come to love the job, but I still hate the application process. Listen, it’s a high honor to be asked to serve and to be appointed by Gov. Patrick to serve the people of Massachusetts, to be part of this, what is often described as the world’s most exclusive club.

It’s a great environment – people are often surprised when I tell them how collegial the senators are with each other. I would love to see some of that collegiality blossom into a little more collaboration and compromise and cooperation. The raw material is there, maybe in time it will happen.

How does the collegiality come through – what have you seen that we can’t see?

Cowan: Well, generally speaking it manifests itself in the degree of warmth and support that I have received as a new senator, even as an interim senator, as a short-timer. Republicans and Democrats alike have indicated to me, said to me or communicated in various ways that now that I’m here I’m a part of this body, and I should be mindful of that and act accordingly and work hard and take full advantage of the experience to represent the folks back home.

You go back to the day I was sworn in – there were Republicans and Democrats in the chamber who warmly greeted me. One of the first was Tim Scott. Since then, I feel like I’ve made some good relationships with certainly folks on my side of the aisle but folks on the other side. I have a deep appreciation for Lindsey Graham. There are many things we don’t agree on, but I feel that that doesn’t mean we can’t be agreeable. We spent some time together in the Middle East on a CODEL. I also spent time with John Hoeven there and I got a sense of who those people were, not as senators, not as politicians, but just regular folk and developed a sense of why they decided to serve in this capacity and the origins of their political thinking and ideology.

This is a place where there are squabbles and fights and disagreements and discord and debate – as it should be – but that shouldn’t define what this institution is and who the senators are. It should be part of the process that yields the results for the good of the country. I think for too much right now that’s become the result and not the means and we have to get back to a point where that is the means to a favorable end for the nation and not just the sum result of our interactions.

You’ve spent a lot of time presiding…

Cowan: Yes, it’s awesome.

Is it, though?

Cowan: Yes, it is. It is. I was surprised when I got here that that was part of freshman responsibility. And I was terrified the first time I was told I was going to preside. When you sit there, and you observe it, either while you’re in the chamber or if you stumble upon C-SPAN, it’s a very ritualistic, regimented proceedings, particularly when senators  say ‘I ask unanimous consent’ and that presiding officer seems to know exactly what to say in that circumstance.

But when your number is called for you to go up there, you are like, whoa, I hope that there is a manual somewhere. Is there a training video for this thing?

But I enjoy it, first of all because the floor staff from both parties and the clerks and the parliamentary staff are exceptional people. They recognize we freshmen who get up there are brand new to this thing. And if you’re a smart freshman, you recognize that these people have seen this and done this a million times, and it’s best to ask questions and listen. They’re very helpful in helping you understand, but also your role and your obligations and often what you need to say.

But here’s why I enjoy it: Because I am experiencing the greatest living civics lesson that one could ever imagine. And I get to sit up there three times a week for an hour at a time and listen to some of the greatest orators, political thinkers of various ideologies opine and argue about the issue of the day, the things that matter most to them, the things that matter most to their constituents, things that are relevant to my constituents and me. And you get to hear both sides. Sometimes there’s a little gap between one side or the other, but you get to hear it.

Sitting up there, I don’t know if all my colleagues do it, but I actually sit there and listen. I listen, because I think in this line of work, I think the smartest thing you can do is listen. Listen to your constituents, listen to your colleagues, listen to experts, stakeholders. Inform yourself so you can make informed decisions. And sitting up in that presiding officer’s chair is a great way to inform oneself.

I don’t agree with everything I hear – on either side – but it helps frame the perspective.

What is the coolest thing you’ve done so far. What was the thing that made you go ‘Wow, I can’t believe I did that, or saw that, met that person?’

Cowan: Can I tell you honestly, the thing I’ll remember most when many of these memories are faded -- I hope this doesn’t sound too hokey -- but the day I was sworn in, I had the pleasure and privilege of seeing the vice president of the United States speaking closely and candidly and respectfully to my mother, a child of the South, product of the Jim Crow educational system.

A woman who was capable of anything, but throughout the formative years of her life was denied too much. A woman who had always told me that no matter what, I could do and be anything I wanted to be. To sit there and observe that conversation, that was the coolest thing I’d ever seen.

Did it ever cross your mind that you’d do something like this?

Cowan: No. No, people have asked me when I was a kid or in school, even in my adult life, did I think about being in the Senate, I tell them six months ago I wasn’t even thinking about being in the Senate.

I owe a lot of this to Deval Patrick, someone I met nearly 20 years ago when I was a relatively young know-nothing lawyer. I’m a slightly older know-nothing lawyer now. And with no particular reason to do so, he became a great mentor and friend of mine and has provided me tremendous opportunity, often when I didn’t even realize the merit of the opportunity.

That said, none of those interactions led me ever to conclude, you know what, I might be in the Senate one day. I loved working with Gov. Patrick, being his chief legal counsel and chief of staff, but I was quite comfortable being a behind the scenes kind of guy. Keeping the trains on time and making sure everything was happening as it needed to happen.

I had to adjust from being the handler to being the handled.

How’s that adjustment been?

Cowan: I’m still adjusting.

And by the time you do you’ll be gone.

Cowan: Yup, I’ll be gone.

Who did you speak with before you got here? You’re one of a four or five guys who’ve done this in recent years. Carte Goodwin, Paul Kirk, George Lemieux, and now Jeff Chiesa from New Jersey. Did you talk to any of them?

Cowan: I talked to Paul Kirk. You know, I knew Paul because when Sen. Kennedy passed away, and Gov. Patrick was called upon to appoint an interim in that capacity.

Were you involved in that?

Cowan: I was, but not as part of the administration at the time. I was still on the outside. I was asked to weigh in a little bit and thought Paul was the right, a great choice. So there’s a little bit of irony that a few years later I’m calling him and telling him, hey, guess who’s going to Washington and what advice or counsel do you have for me?

And these are more my words than Paul’s, but the essence was there: When you go down there, you’re going to be an interim senator, and you won’t be there for long, but don’t let that define how you conduct yourself when you’re there. You’re going to be a senator representing the people of Massachusetts, go there being a senator representing the people of Massachusetts. Be a senator in full, because that’s what they deserve.

Is there anything that has frustrated you about this place?

Cowan: Procedurally, the filibuster rules flummox me. If you’re observing all of this from the outside, it’s hard to imagine why if you get 51 votes you don’t win the day. And so I am coming to understand ... the rhyme and reason behind the 60-vote super-majority. It’s frustrating, because you look at the Toomey-Manchin gun background check bill, the vote had 54, 55 yesses. In most math classes that’s a majority. So I’ve seen some good legislation lose because it couldn’t get 60 votes. I’ve seen some bad legislation lose because it couldn’t get 60 votes.

Now, I’m very mindful of those people who say that it’s really there to protect the minority so that one does not run roughshod over the minority. Intuitively I get that, but I also say that this is a democracy, and our Founding Fathers came up with a pretty good system here that’s still serving us well today. And at the end of the day, we’re answerable to the people, and if people don’t like the decisions that the majority make, the people will respond.

And I know some of my colleagues have called for filibuster reform, the so-called 'Nuclear option.' I don’t know if that is the right answer – I really don’t. There’s a larger debate that goes on around here about regular order. I suppose they could, but if people aren’t willing to use regular order to make things work, what good is regular order?

It’s also been interesting to observe what I’m going to call the influence of campaign financing. People often ask me if the system is broken. I tell them I actually don’t think our system is broken writ large, that is our system of democracy is the greatest governmental system ever created and is as good today as it ever was. But it is only as good as the people who are in power to use it or employ it and they’ve got to want to make it work.

If there is a part of the system that is completely out of whack, it’s campaign financing. I think money has such a pervasive, pernicious influence on governing around here that it’s getting in the way. And perhaps it’s not even money, it’s the fear of what may happen to you, who may mount a challenge against you if you’re seen as capitulating or compromising too much or violating the principles of your given base.

I do think that’s getting in the way of Congress being as effective as it can be, because all the tools are there for us to be as effective as the American people demand and need us to be.

I think Citizens United, with all due respect to the Supreme Court, was poorly decided and has had detrimental influences on our government well beyond that which they might have even considered, if they considered it at all. And I think those implications are going to be long-lasting and it’s going to get worse before it gets better.

Both sides, both major parties are going to play the game, because those are now the rules of the game. But I fear that the loser of the game is the American people at the end of the day, because you get more and more polarized political players, who are hewing to the most extreme elements, because those are the ones who come out for the primaries, those are the ones who fund the super PACs. And if you campaigned on those principles, it’s harder for you to govern on a more moderate principle governing towards the middle, where frankly most of the nation still resides."

You get to keep your status once you leave, right?  You could come back anytime?

Cowan: That’s an interesting question. I’m told I can keep my title, I don’t know what kind of status comes with that. I can ensure you in my home, the title of senator does not afford one much status.

Apparently you do get some privileges for life, unless you become a registered lobbyist or something, I’m told. I don’t know where my fortunes will take me after this, I’m not sure of the value of those lifelong privileges.

I strongly suspect I will not ask the people to address me as senator for the rest of my life. I kind of like Mo, it’s served me well."

It’s been noted that you’re here at a time when the Senate Republican conference is slightly more racially diverse than the Senate Democratic caucus.

Cowan: Is that so? Based on?"

Well, Marco Rubio and Ted Cruz and Tim Scott versus yourself and Robert Menendez.

Cowan: Did you forget Sen. Hirono?"

Okay, Sen. Hirono also. Good point. So maybe you’re even. But you’ve heard it said that the Democratic Party, considering who it represents and its base of support, lacks more people of color in Congress.

Cowan: Here’s what I think about that: First of all, I think it’s good that the Senate is starting to be more representative of the population writ large. And the fact that you have Sens. Rubio, Cruz, Scott, for example on the other side of the aisle, to me as someone who enjoys the political process, who thinks people should be politically engaged, as someone who believes in our system of government, it’s a good thing.

I also think it’s a good indicator and a sharp reminder to everyone that just because people may share an ethnicity or be of the same race or gender, we don’t all think alike. And we need to get out of that mindset. There are as many political debates – conservative and liberal debates – in the black community as there are anywhere else.

But here’s what I’d say about it to both Democrats and Republicans: You should take no community or group of people for granted. Do not assume the votes will follow you, regardless of what you do. Every political party, every politician, everyone who wants to be an elected official, must work for the vote, certainly for an individual or group. And I think we are treading in dangerous territory if we take any group – if you want to group people together by race, ethnicity or gender – for granted.

I would tell my Democratic colleagues, if you want to continue to enjoy the majority of the African-American vote, or the Latino-American vote, you have to continue to engage with those communities and ensure that the national and state and local platforms are reflective of the need, desires and concerns of those constituencies, just as you should for any other group. If the other side is smart, they’ll do the same.

I guess the RNC is planning to invest a significant amount of money in doing that. We’ll see what that yields, but sometimes it doesn’t take a lot of money, it just takes a willingness to sit and listen to people, meet them where they are and understand how they work and live and the challenge they face daily and try to convince them that your policies and platforms are consistent with that.

No one owns the black vote, no one owns the Latino vote, or the lesbian and gay vote, or any other vote. You better earn it. And you should always recognize that you can lose it.

Your relationship with Tim Scott, you mentioned that you’ve talked a lot. What’s he like? I ask, because he avoids the press. And he’s in a different position than you because he’s actually running for his seat.

Cowan: I like Tim, again, our political ideologies do not mesh, but I think he gets to where he is honestly and earnestly. He has an interesting life story.

Probably 90 to 95 percent of the things Tim Scott and I may not see eye-to-eye on, but he was willing to say, let’s at least get to know each other to determine if there is 1 percent of things that we could work together on. Even if we didn’t agree on those issues.

Real quick: Bowties – how many do you have?

Cowan: The [Senate] pages asked me this once and asked if they could raid my collection. I haven’t counted, but I must say about three dozen."

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