There’s a new poll out in Iowa, and I was tweeting about it, so I figured I might as well turn it into a post. Remember: I’m blogging because I’m up and thinking about it, but it’s a single poll, and relatively small random variations could be showing up — it’s the first Iowa poll in several days, and so we have to wait for a couple more to get a better sense of everything. Remember too that the Iowa caucuses are notoriously hard to poll.

The top line doesn’t show much: Ron Paul has a small lead over Mitt Romney (24 percent/20 percent), and then there’s a modest gap before a bunched field for the other spots: Gingrich 13 percent, Bachmann 11 percent, Perry 10 percent , Santorum 10 percent. That leaves

Perhaps the biggest single number in the entire poll is Newts favorable/unfavorable ratings, which have totally tanked: he’s at 37/54. PPP is making a lot of Santorum’s favorable/unfavorable, which are the best in the field, but while he definitely could finish strong, I don’t really see anything to convince me that he’s in better shape than Bachmann (only slightly worse numbers) or Perry (who will outspend both of them). Remember, organization matters, too. I suspect that Newt’s organization is also the weakest. I’d like to know more about how many caucuses will have someone speaking for the various candidates.

Mind a little speculation? Here’s what I see, combining the PPP poll and Nate Silver’s (topline-based) prediction model:

1. Any of the six could wind up with a top three finish in Iowa. Newt is least likely, in my opinion, but certainly could hang on and manage to do it.

2. Any of five — all but Newt — have a realistic chance of actually winning Iowa.

3. Of the six, only Ron Paul is a lock to finish in the top three. Anyone else could finish as low as 6th place, although I’d be a bit surprised if Romney did. It’s hard to see Paul finishing worse than third.

4. Expectations do matter and are somewhat affected by objective factors (that is, pre-caucus polling vs. caucus results). So one of Perry/Bachmann/Santorum are still likely to be a significant story if one of them finishes third (likely), and even more so if one winds up second or, obviously, first.

5. On the other hand, as Silver just tweeted, there could be bandwagon effects if one of that group is perceived as breaking out in the next few days. In particular, that’s probably where Newt is especially vulnerable; I suspect (and the crosstabs support this some) that a lot of conservatives and evangelicals parked with Newt when he appeared to be the most likely conservative/social conservative alternative to Romney (and Paul). That perception was probably still out there right now. If it collapses, his support could collapse, too.

6. Indeed, while he could still finish as high as second, if I had to bet on one of these six to finish behind the others my money would be on Gingrich.

7. But it’s one (new) poll! I’m speculating! More information will be available soon.

Last caveat: this is only about Iowa. Iowa results matter, but how much and how depends on lots of other things.

[Cross-posted at A plain blog about politics]

Jonathan Bernstein

Jonathan Bernstein is a political scientist who writes about American politics, especially the presidency, Congress, parties, and elections.