I know there's an argument that says that Republicans are cool because of something, but in popular culture whatever that argument is doesn't seem to hold water. Take for instance this 'Rock the Vote' contest on MySpace. The winner gets to perform at the Democratic National Convention. Two questions arise, 1) why is it desirable to perform at the DNC (as opposed to the RNC) and 2) why is it that the DNC is bringing in rock bands to perform? I believe that both of these point to a critical flaw in the way the GOP has marketed itself - particularly to the younger, hipper, more tech savy portion of society. The GOP does not have a considerable web presence - especially compared to the gauntlet that both the DNC and the Obama campaign have put up. A nominee that says he barely understands computers isn't helping either. Because of this the Dems have found a way to connect with young voters in a way the GOP hasn't. Since the DNC looks more cool, those younger voters are more likely to listen and be swayed by the arguments of the left. It goes beyond simply having a web presence, but I think that this one area along with things like the contest mentioned above are emblematic of why the Democrats are seen as so much more cool than Republicans.
I am in no way saying that we should replace competence for coolness. I simply believe that it's possible to have both with Obama being a living example of this and McCain being the ultimate contradiction. The GOP has a lot of money, so why can't they hire a competent marketing strategist to at least get a cool factor for the party, if only to bring in younger voters - even if they seem incapable of nominating somebody that is completely competent (and cool).