Here's a conundrum: what should Clark's supporters in Iowa do? Most polls show about 3% of Iowans supporting Clark. With the race seemingly so tight, they could make the difference and swing the results if they backed another candidate.
My personal view: the more the field is cleared for Clark to position himself as the lone alternative to Dean (the only competitor who already has resources to stick around to the end), the better. Therefore, the person to knock off is the one who presents the most stiff and direct competition to Clark. In my mind, that's Edwards, because he can draw support away from Clark in key Feb. 3 states in the South, whereas Kerry and Gephart have less roots, cash, and/or organization to make that happen.
Since Dean is already established nationwide, and since Gephart is less of a threat, I would suggest to Clark supporters in Iowa to prop up Kerry, to knock Edwards as far down the ladder as possible, making him less relevant in New Hampshire and having no momentum going into Feb. 3.
I could make a minor argument to support Dean to blow the entire rest of the field out of the water and make it a two-man race, but with the numbers so tight in the polls, its iffy they could add any meaningful separation to a Dean victory (if that even happens). Some might also suggest sticking with Clark to show grassroots support, or to build morale among Iowa volunteers for later campaign efforts.
I invite comment on the ethical considerations behind this - is it okay to "push" the election one way or the other if your candidate isn't in it? Some of you might take issue with it, but put in perspective of the caucus, the system is set up to encourage voters to move to major candidates if their guy isn't registering. People have a right to make their vote "count" somehow.