Are you hip if you try hard to be? The answer is usually no, and that's what some young voters may conclude about the web efforts of the two leading presidential candidates. The G.O.P., at 2004NYCGOP.ORG, is sponsoring a contest, Stand Up and Holla, inviting young entrants to write about the President's call to community service. The prize? A trip to the convention. John Kerry's site, JOHNKERRY.COM, meanwhile, offers up remixes of Kerry one-liners sprinkled over funk and jazz beats.