Many people have taken the 2004 Iowa caucus and New Hampshire primary results as proof positive that the candidate winning here will develop enough momentum to carry him or her through the entire nominating process.  While that obviously happened with John Kerry’s dramatic turnaround in New Hampshire following his win here, it is by no means a rule.

Historically, Iowa and New Hampshire have almost always differed in their choices.  Not counting sitting Presidents or Vice Presidents, Jimmy Carter was the last time that Iowa and New Hampshire agreed on anyone for either Democrats or Republicans (and technically Iowa voted for Undeclared over Carter).  If anyone other than Kerry had won the Iowa caucus in 2004, that streak would almost certainly have remained intact.

No, what 2004 taught us was that soft support in New Hampshire never really goes away.  Kerry was the default frontrunner there for half of 2003, with Dean eclipsing him around the middle of the year.  Even after moving all of his resources into Iowa, Kerry was still polling in second place.

After winning in Iowa, those 25%-30% of people who supported him earlier in the year suddenly remembered that they still supported him.  That, combined with an important but not overwhelming general boost from winning the caucus, led to his win there.

If John Edwards had won the Iowa Caucus, Howard Dean would have probably picked up New Hampshire, and the 2004 nomination fight would have been a lot more interesting (I’m just going to say for fun that Edwards probably would have ended up winning – he’s just a better all around candidate than Dean).  Instead we saw that Kerry rebounded, and took the combined momentum of back to back wins into a dominating performance throughout the rest of the season.

What does this tell us about 2008?  Right now Hillary Clinton is the John Kerry of New Hampshire, with high natural support that is persisting even with other campaigns active in the state.  If she exceeds expectations in Iowa, she should recapture those voters even if they stray in the meantime.  She is also much less likely than Dean to dramatically underperform in Iowa, which means that her New Hampshire supporters won’t be as shaken as Dean’s no doubt were.

2008 is going to be a lot different than 2004 though, with all three first tier candidates regularly polling in the double digits in early primary states.  Both Edwards and Obama have the potential to string together back to back wins, though it seems unlikely right now that a surprise Iowa showing by any of the second tier candidates would lead to dramatic movement in New Hampshire.  It’s still early, but with the campaigns moving as fast as they are this kind of analysis is appropriate now when it wouldn’t have been in February 2003.  Al Gore would shake things up, but other than that, or someone (probably Obama) making a dramatic gaffe, it looks like our field is pretty well set.