So, what do the first caucuses and primaries tell us about the last glass ceiling in American Presidential politics?
Is it race, as some surmise after New Hampshire? Is it gender, as some concluded after Iowa? Is it both?
Or do the results demonstrate that neither is meaningful anymore?
Women outvoted men 57-43 per cent in both Iowa and New Hampshire, but with opposite results. In Iowa, they broke for Obama by 35-30 per cent, and arguably, gave him the victory. In New Hampshire, the state with the second highest percentage of women in its legislature (nearly 36 per cent,) they went strongly for Clinton by 46-29 per cent, more than enough to give her the margin. Conclusion? Memo to the media: take nothing for granted.
Neither state of course, has a large bloc of African-American voters. We will have to wait for South Carolina and other states to see how the black vote actually breaks in a 2008 presidential primary. Again, media, take nothing for granted.
When it comes to voting, as in sports, the differences between men and women are more telling than between whites and blacks. Rightly or wrongly, men hold women to a different, more demanding standard when judging whether they are fit for the presidency.
Whether they admit it or not, men ask whether a woman candidate for the White House has the strength and emotional stability to face down a major international threat, or stand up to the demands of the job. They rarely ask such a question about a male candidate - if the issue arises with a man, he is toast, anyway.
Hence the fuss over Hillary's emotional moment in the diner in New Hampshire, and in the Manchester debate, when she admitted to hurt feelings over the question of whether she makes the grade in "likability." The primary results suggest that many women found those to be humanizing moments. Some men probably saw them as signs of emotional weakness.
It was a classic demonstration of the unique dilemma women face in running for national office. They have to be demonstrably tough, but not excessively so; visibly human, but not vulnerably so.
When it comes to race, the issues are more subtle. A quarter-century ago, Tom Bradley, then the mayor of Los Angeles, clearly was hurt in his gubernatorial loss to George Deukmajian by racial considerations.
Will the "Bradley factor" apply to Obama this year? There was little-to-no evidence of it in Iowa or New Hampshire. Remarkably, race did not seem to be an issue.
But, yet again, take nothing for granted. There are surely many American voters who, in the privacy of the booth, won't pull a lever for an African-American, any African-American for president. Similarly, there are voters who will specifically support Obama because of his race, feeling that the moment is long overdue.
No doubt there are also voters, mostly men, but women, too, who flat-out won't vote for a woman for president. And we already have seen that, at least in New Hampshire, women will come out in unusual numbers to support a female candidate.
What we don't know at this point is, plus-and-minus, how many such voters there may be. They are not likely to level with pollsters about it.
But we are about to learn when they actually vote. Unlike any race before, this year's presidential contest is going to demonstrate whether and which glass are ceilings still in place in American politics.
Terence Smith is a journalist and former media correspondent for The NewsHour with Jim Lehrer. His website is terencefsmith.com