The Nevada entrance polls provide fascinating insight into the Democratic battle between Hillary Clinton and Barack Obama.

Clinton won decisively among women (51%-38%), while Obama won narrowly among men (45%-43%). But the stunning number is the percent of voters from each group: 59% of Nevada's voters were women, while 41% were men.

This turnout was even more lopsided than Iowa and New Hampshire:

Unfortunately for Obama, the gender gap has flipped from Iowa - where it favored Obama - to Nevada, where it favored Clinton.

In Iowa, Obama won men by 12% and also won women by 5%. But in New Hampshire, Clinton won women by 12% while Obama won men by 11%. In Nevada, Clinton won women by 13% while Obama won men by only 2%.

There's an historic narrative behind these numbers: women were hesitant to embrace Clinton initially, but that changed dramatically in the five days between Iowa and New Hampshire. And once women embraced Clinton in New Hampshire, a lot of men followed suit in Nevada.

A lot of ink has been spilled on what switched women in New Hampshire. Clinton was excellent in the Saturday night debate, both factual and funny when asked about her "likability." Obama's dismissive "you're likable enough" remark hurt him tremendously. That Sunday, Clinton connected powerfully with women when she answered "it's personal" when asked about the strain of the campaign. Meanwhile the misogyny in the Corporate Media ("the Tweety Effect") caused women's blood to boil. And as the narrative emerged that Obama could knock Clinton out of the race with back-to-back wins in Iowa and New Hampshire, women decided Clinton had earned a real shot at the Presidency.

Another factor is campaign organization and the "ground game." Obama's innovative team did a brilliant job of turning out new voters in Iowa, but Clinton's experienced team did an equally good job of turning out pro-Clinton voters in New Hampshire and Nevada.

Of course gender isn't the only powerful force at play in the battle between Clinton and Obama - race is also important. And polls show black voters who initially embraced Clinton have switched strongly to Obama. But a majority of black voters are also women, and more black women stuck with Clinton than black men.

Next week's South Carolina primary will focus more on race than gender, because half of the Democratic voters are black and Obama's lead is solid. But from Florida onwards, black voters will be more like the 15% of the Nevada electorate, and they simply won't be a large enough group to overcome Clinton's lead among women, especially if women are 57%-59% of the voters.

So at this point Clinton has the edge, but the race is close enough that Obama is likely to win some primaries and we could end up with a brokered convention...