The 2008 US Presidential Election was historic for many reasons. One of the most obvious is that it led to the election of America's first African-American president, but it also had other things that made it significant. It was the first election since 1952 in which none of the candidates involved were an incumbent president or incumbent or past vice-president. It was the first time in United States history that two sitting Senators ran against each other. And it was the first time that major party candidates from Alaska and Hawaii ran in an election.
But before the general election, there was a primary election, and in retrospect, it might have been just as important in the long run. While the Republican Primary was concluded fairly quickly, the Democratic Primary was a long and complicated struggle, being contested until the finish. For the Democratic Party, there had not been a contested primary since 1992, and the first truly contested primary contest since 1976. Since it was expected to be a hard election cycle for the Republican Party, many candidates entered the race, although many of them were considered long-shots.
At the beginning of the race, the leading candidate was Hillary Clinton, former First Lady and Senator from New York. Slightly behind her was Barack Obama, Senator from Illinois, and John Edwards, Senator from North Carolina and John Kerry's running mate in 2004. Other candidates included Chris Dodd, Joe Biden and Bill Richardson. However, fairly early on it became a three person race, and after John Edwards did poorly in South Carolina, a state that he was expected to do well in, it became a two-person race between Hillary Clinton and Barack Obama. By Super Tuesday, presidential primaries are usually settled in all but name, but by that point, the primary was just beginning. Over the next few months, Obama and Clinton traded electoral victories in different states, with Obama slowly edging above Clinton, both by winning more contests and by collecting "superdelegate", party leaders who can select whoever they choose.
The contests were all proportional, and the rules for selecting delegates were somewhat arcane, with it being possible to win a majority of delegates in a state while getting less of the popular vote than your opponent. Obama's success also had a great deal to do with organizing and getting out his supporters in caucus states.
But the real story isn't in those numbers, it is in the fact that Obama chose to compete in gaining delegates at all.
Imagine that in a general election, the Democratic and Republican candidates held elections in three to five fairly small states. At the end of that, they would see who had the most money and the most good media coverage that week, and if their opponent seemed to be doing better, they would concede the election to them. While it seems ridiculous to suggest that a general election would be settled that way, that is how primaries have traditionally been settled. After the first few contests, the leading candidate, even if their lead was rather minor, would be acknowledged as the "front runner" with the "momentum", and the other candidates would usually step out of the way, with varying degrees of grace.
So what Obama did was to look at the primary as an actual election, and instead of trying to get crowned as "inevitable", he did the math of seeing just how many delegates he could gain by doing very well in, say The Virgin Islands and Idaho, two areas not usually considered to be of vital importance for the Democratic Party in Presidential elections, primary or general.
In addition, whereas in past elections, the electorate had moved more or less in unison, the 2008 Primary was about demographics. Obama's supporters were mostly minorities, young people, urbanites and the college educated, while Clinton's supporters were seniors, union members and residents of the Rust Belt. Both Obama and Clinton didn't attempt to win all the members of their party, but instead focused on winning participation amongst their base. In the end, Obama's ability to organize his supporters in caucus states, many of them previously considered marginal and unimportant, was probably what led to his final victory in the Primary.
Why this election was so historic, especially in light of the current Republican primary contest, is that I think that the trend of primaries being treated as actual elections, and not as popularity contests settled by the media, the party leaders and the candidates themselves, will be the new way that primaries are run. It is hard to say, of course, since each election is different and candidate quality varies, but I do believe that the 2008 Democratic Presidential Primary is a sign of how primary contests will now be settled.