Iowa Turnout. Who has the advantage?

There are a couple of numbers floating around today concerning turnout in tonight's Iowa caucuses and the expectations for who will come out victorious there. The thinking from within the campaigns and among outside observers is that high turnout is good for Obama and Huckabee. The Fix over at The Washington Post has cited the 200,000 caucus-goers as the line of demarcation for Obama. If the number tops that figure the advantage goes to the senator from Illinois according to his campaign (see here and here for more). As The Fix points out though, that is based on the idea that the growth in caucus participation is weighted toward Obama when in fact the distribution between the top three Democrats could be more even. The second choice voters are still important in Iowa as well. If their candidates don't reach fifteen percent, who do they back? Some polls seem to indicate Edwards and others Obama (The Edwards link is a little dated, but NBC reported as recently as Sunday night (Dec. 30) that Edwards led for the second choice folks.). Now, if the new caucus participants go for Obama and the supporters of the "non-viable" candidates align behind Edwards, will Hillary sink to third?

On the Republican side, 80,000 is the mark for Romney and Huckabee. The Romney camp has stated that anything over that number of caucus-goers could spell trouble for the former Massachusetts governor. Under that scenario, Huckabee's grassroots rise would likely bring enough new voters to the caucus to provide him with a victory.