Two historic candidates

Here's the big problem though. It's all very well bring out millions of extra voters, but it's only beneficial if these voters check the right box in November. In the past nomination fights have generally been over after a small proportion of the scheduled contests, preventing a divide opening up in the party. Those contests that were settled at the convention might appear to have been very divisive, but they were divisive largely only among a small elite within the party. The divide that has opened up this time is between literally millions of Democrats. That's not a divide with historical precedent, and it's not a divide that's going to heal anytime soon.

The prolonged primary season has racheted up the tensions between two groups of supporters. In fielding two historic candidates the Democratic Party should not be surprised that they have generated intense and passionate support. The problem is that both camps have become very attached to the historic nature of the candidates - the first serious female contender and the first serious African American contender - and deeply resent the fact that one of these candidacies will not succeed. No wonder then that the accusations of sexism and racism have flown in the last few months.

The Democratic Party has put itself in a situation where one viable historic candidacy will not be given the nomination. As a result, many Clinton supporters feel a deep sense of betrayal. This dramatic YouTube clip aptly demonstrates the huge challenge facing Barack Obama in reuniting his party in time for November. The strength of feeling brought out by months of campaigning isn't going to be redirected in a hurry. The primary season might be (almost) over, but the Democrats still have a big problem to solve.