Today is International Women's Day. And, of course, that got us to thinking about when (and if) America will have a female president. (The Fix is nothing if not an unrepentant political obsessive.)

If Hillary Clinton doesn't run in 2016, it's possible that there won't be another woman who is a serious contender for president.

A look at the 2016 presidential fields suggests that if former Secretary of State Hillary Clinton decides not to run -- and she has left the door open but suggested she is not inclined to make another bid -- there is a dearth of women who a) might run and b) would be considered top-tier contenders if they did.

Our first rankings of the 2016 field for both parties, which we did in the last month, showed few women positioned to be major players in the contest.  No women made the top 10 in our Republican ratings. Three women not named "Hillary Clinton" made our top 10 on the Democratic side but they ranked #7 (Janet Napolitano), #8 (Kirsten Gillibrand) and #10 (Elizabeth Warren), respectively.

That means that if our initial rankings are correct -- and that's big "if" -- there will be no top tier female candidates for either party in 2016 if Clinton takes herself out of the race.

That's a remarkable thing to ponder given that in the aftermath of the 2012 election there are 20 women serving in the U.S. Senate and 77 women serving in the House -- both record highs, according to figures kept by the indispensable Center for American Women in Politics at Rutgers University. (Women comprise 18 percent of all elected officials in Congress.)

Sara Taylor Fagen, a former Bush White House political director, while acknowledging the gains women have made in the House and Senate in recent years, noted that 80 percent of the Senate is still male, adding: "What other industry has a worse number?  Even the business world has a greater percentage of female senior executives."

At the state level, the number of women in office has dipped slightly since the early 2000s but females still comprise more than one in five of all statewide officeholders.

Chart courtesy of the Center for American Women in Politics.
Chart courtesy of the Center for American Women in Politics.

Despite those gains for women in elected office, it's hard not see a major drop-off in potential women presidential candidates if Clinton doesn't run.

Some of that dropoff is due to the fact that Hillary is so accomplished (First Lady, Senator, Secretary of State) that comparing her to anyone --male or female -- leaves the other person looking a bit wanting.  She is simply a unique force in American politics.

Another factor is that many of the brightest female stars in both parties may well be on a 2020 course rather than a 2016 one. New Mexico Gov. Susana Martinez is widely regarded as a potential national candidate for Republicans but is only in her third full year as chief executive.  Ditto Democrat Kirstin Gillibrand, who has been serving in the Senate for just four full years.  Or even Warren, who was just elected to the Senate in 2012 (Of course, it is also true that neither Barack Obama nor George W. Bush had resumes chockful of years of experience in elected office before running and being elected president.)

Mary Matalin, a prominent Republican consultant, suggested another reason for the dearth of prominent females candidates not named Hillary Clinton.

"Women are blessed to have dispositions that prioritize results over credit," said Matalin. "They know they can have more impact with less hassle and more readily control their schedules/lives by being in the process rather than needing to be the principal."

Whatever the reason, it is uniquely possible -- looking at the field we would call it likely -- that if Hillary Clinton doesn't run in 2016, it will be at least 2020 until a woman is considered a top tier candidate for president.

And that race will take place more than a decade removed from Clinton uttering these now-famous lines in ending her 2008 campaign:

"Although we weren't able to shatter that highest, hardest glass ceiling this time, thanks to you, it's got about 18 million cracks in it. And the light is shining through like never before, filling us all with the hope and the sure knowledge that the path will be a little easier next time."

The question now is: Will it be?