It's still really early. My goodness, more than a few foibles and events might happen before the 2008 Convention.
Heck, with the Internet, you might think the cost of campaigning might drop precipitously.
Someone (sorry I can't cite the source FReeper) suggested that the Dems are in silent cruise mode, hoping that a sore GOP beats each other to shreds to set up a 2008 cakewalk.
Keep the powder dry.
Rudy may sell in the Upper East Side or even New Hampshire and Maine but no way in hell will GOP Voters in the South, West and Midwest vote for that cross dressing, baby killing, two timing RINIO.