Hillary Clinton's victory speech following the South Carolina primary was the campaign moment her supporters had been waiting for. As Chris Tognotti on Bustle observed, 'it's tough to deny her skill as a forceful and fiery orator, and never more so than when the wind's at her back'. Clinton spoke warmly and easily on education, entrepreneurship, and the need to alleviate student debt but, as Tognotti wrote:

...none of that had half the emotional resonance and impact as when her speech turned to race. In addition to pledging additional support to historically black colleges, Clinton achieved perhaps the most pitch-perfect emotional tenor of her entire campaign in discussing racial injustice, citing several high-profile examples of slain black Americans.

The 15 minute speech (which you can watch in full here), could well come to be seen as a turning point in this presidential race. National polls such as this one from CNN, released on Monday, show Clinton pulling ahead of Bernie Sanders (55% to 38%). The mathematics of the primaries is also playing her way, and her delegate count is sure to shoot up over the next 24 hours as the results from Super Tuesday are finalised. As we wait for those results to come in, it's worth taking a look at whose votes are giving Clinton the edge in the primary race. As CNN notes:

There are sharper demographic splits among the Democratic electorate than on the Republican side. Men, younger voters, independents and liberals are all about evenly split between Clinton and Sanders, while Clinton's lead rests on large advantages among women, older voters, Democrats and moderates.

Much was made of the fact that 55% of female voters in New Hampshire chose Bernie Sanders, while 44% voted for Clinton. However, as Barbara Norrander, a professor in the School of Government and Public Policy at the University of Arizona explains in this opinion piece for the Washington Post, that result did nothing to dent the gender gap in Clinton's support base. This gap, Norrander explains, measures 'how well Clinton did among men versus how well she did among women'. Doing better among women has been a feature of the Clinton vote for quite some time, Norrander wrote:

Even in New Hampshire, Clinton did better among women than men. There her gender gap was even larger: 12 percentage points. Clinton won the votes of 44% of women and only 32% of men. The gap was the same in the Nevada caucuses: 13 points, with 57% of female and 44% of male Democratic voters saying they chose Clinton.

In other words, Clinton’s 2016 gender gap so far is much like her gender gap in the 2008 presidential primaries, when 9% (on average) more women voted for her than did men.

Drilling down a bit further into the women's vote, here's a group you may not have heard much about in this election: single American women. They are a considerable electoral force, as explored in this excellent feature by Rebecca Traister in the New York Magazine:

In 2012, unmarried women made up a remarkable 23% of the electorate. Almost a quarter of votes in the last presidential election were cast by women without spouses, up three points from just four years earlier. According to Page Gardner, founder of the Voter Participation Center, in the 2012 presidential election, unmarried women drove turnout in practically every demographic, making up almost 40% of the African-American population, close to 30 percent of the Latino population, and about a third of all young voters.

These women tend to be left-leaning (67% voted for Obama in 2012 vs 31% for Romney), and may well deliver Clinton into the White House, as long as enough married women, black Americans and other demographics back her in the primaries. In early voting States, single women have favoured Sanders but poll after poll shows those who lean Democrat are overwhelmingly likely to get behind whoever eventually emerges as the successful nominee. Now that the balance of power in the Supreme Court also hangs in the balance, single women, known to be politically active, are likely to turn out in droves come election day. If Clinton is on the ticket, that will be the box they are most likely to tick.

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