In an interview that will air this Sunday on MSNBC's PoliticsNation, Democratic presidential front-runner Hillary Clinton condemned House Majority Leader Kevin McCarthy for saying the ongoing investigation into the Benghazi attacks hurt her campaign.

"When I hear a statement like that, which demonstrates unequivocally that this was always meant to be a partisan political exercise," Clinton told PoliticsNation host Al Sharpton, "I feel like it does a grave disservice and dishonors not just the memory of the four that we lost, but of everybody who has served our country."

McCarthy's comment came during a show that's typically as friendly to Republicans as Sharpton's shows have been to Democrats -- Hannity on Fox News. Egged on to name something that the party had actually done for its base, McCarthy cited the creation of the Select Committee on Benghazi.

"Everybody thought Hillary Clinton was unbeatable," said McCarthy. "What are her numbers today? Her numbers are dropping."

Sharpton gave Clinton two chances to hit back at Republicans, asking if McCarthy's comment was the sort of thing that causes voters to be cynical about politics. "When this happened," Clinton said, "I immediately said, I want an independent review board."

That was a reference to a State Department probe of the attacks that Republicans have derided as slapdash and inconclusive -- a probe that did not even reveal that Clinton had routed e-mail through a private server.

The transcript of the exchange is below.

SHARPTON:  Let me raise another issue.  House Majority Leader Kevin McCarthy, he said this week, quote -- I'm quoting him -- "Everybody thought Hillary Clinton was unbeatable, right? But we put together a Benghazi special committee, a select committee. What are her numbers Friday? What are her numbers today? Her numbers are dropping." That's the quote.

CLINTON:  Um-hmm.

SHARPTON:  You're expected to testify before the Benghazi Committee on October 22. What's your response to McCarthy's comments?

CLINTON:  I have to tell you, I find them deeply distressing. I knew the ambassador that we lost in Benghazi. Along with him, we lost three other brave Americans who were representing us in a very dangerous part of the world.

There have already been eight investigations in the Congress. One independent investigation. We have learned all we can learn about what we need to do to protect our diplomats and our other civilians and we need to be enforcing and implementing those changes, which is what I started and what Secretary Kerry has continued.

So when I hear a statement like that, which demonstrates unequivocally that this was always meant to be a partisan political exercise, I feel like it does a grave disservice and dishonors not just the memory of the four that we lost, but of everybody who has served our country.

We've had lots of different situations, as you know so well. We've had embassies run over. We've had them blown up under Ronald Reagan, under Bill Clinton. We've had lots of attacks where we lost Americans or foreigners working for America, under George W. Bush. We can go back and there's a wall in the State Department, there's a wall in the CIA where we lost those civilians we lost.

It's never been turned into a partisan political battle by the majority in Congress the way the Republicans in this Congress have done. And I just wish that they would really start tending to the people's business, deal with the many problems that we face and figure out how we're going to move our country forward.

You know, I -- I really regret the way that they have treated this serious matter.

SHARPTON: There's a lot of cynicism, a lot of people don't trust what's going on in government. Does this add to it, when you hear a statement by the majority leader? Does this add to the kind of cynicism that many of us are trying to counter?

CLINTON: I think it does. I mean when this happened, I immediately said, I want an independent review board. I want to know everything that we could have done differently. I want to change the procedures. I took responsibility because I wanted us to get to the bottom of what we could understand about that attack.

And that's been my position from the very beginning. When I was asked to testify before this committee, it was after a year of my asking to go testify, because I said I'd be willing to go. I hope they actually ask me about Benghazi and what happened and what we need to do better to protect our people while we still are in dangerous parts of the world.