A few years ago, I authored a column for Campaigns & Elections Magazine on the topic of "Dress for Political Success" (here's the PDF), so I feel somewhat capable of addressing the sartorial conundrums that come up on the campaign trail.
Despite the fact that the Boston Globe recently noted the trend of politicians sporting blue neckties, a good friend of mine recently pointed out the trend among Dems of eschewing the tie. As my friend notes:
The tie-less, open collar thing is a real trend among Democrats. The only Democratic candidate you can find wearing a tie on their front-page/blog is Bill Richardson. You’ve seen Biden’s page. Then…
... At least they aren’t “draping” their sports jacket over their shoulder. I HATE that!