The latest Des Moines Register poll is out, and it shows Hillary building a significant, if hardly daunting, lead over John Edwards and Barack Obama: 29-23-22. The poll has Edwards dropping six points since May, when he led the field, something the Register attributes partly to the flap over his $5 million North Carolina home, his work for a private equity fund that invests in subprime mortgages, and reports of his $400 haircut. The corresponding article suggests Edwards has taken his biggest hit among union members, though there aren't any numbers to quantify the effect. Despite her lead, Iowa voters seem to have real electability concerns about Hillary--something that could create a big opportunity for her rivals in January. According to the Register, "Clinton's reputation as a polarizing figure was cited as a factor by 63 percent of caucusgoers supporting a Democrat other than the New York senator." One person to keep an eye on is Joe Biden, who's up from 3 percent in May to 5 percent in this poll. Biden is reportedly making a real push in Iowa. And, as Bill Richardson fades amid his serial gaffes and less-than-impressive debate performances--he's down from 10 to 8 since May--Biden could emerge as the person most likely to crash the first-tier party. (Even if the likelihood isn't that great.) On the GOP side, Romney holds steady in first at 29 percent, almost exactly where he was back in May. The main difference here is second place: Rudy Giuliani and John McCain were basically tied for second back then. Now Fred Thompson occupies second by himself at 17 percent, while Giuliani has faded to 11 percent and McCain to 7. The person to keep an eye on here is Mike Huckabee, who sneaks into third at 12 percent. I'm on record saying Huckabee can compete in Iowa, and I'm sticking with that prediction. Among other things, this detail stood out for me in the Register write-up: "Among the one-fourth of likely caucus participants who say their minds are made up, Huckabee comes out on top with 19 percent, followed by Romney at 16 percent and Thompson at 15 percent." Numbers like this make me think Huckabee could take second in Iowa. When the governor flashes that winning smile on caucus night, just remember that you heard it here first. Update: A Democratic strategist writes in to take issue with my focus on Biden and Richardson. As he points out, moving up or down two points in a poll with a margin of error of 5 isn't anything to get excited about. Fair enough. It's really just a hunch I've gotten from observing the two candidates of late, for which the Register poll provided some tentative (alright, very tentative) support. Update II: Another Democratic strategist writes in to protest that Biden line. Since I'm guessing it stuck in the craw of a number of readers, allow me to clarify a bit more: The point was that I think Biden, rather than Richardson, is likely to take fourth in the caucuses. And, on the off chance that one of the three first-tier candidates stumbles badly and Biden lands some hefty endorsements from the local media (which I've heard is his strategy), maybe he gets up for third. But that's pretty much it. The point was not to suggest that Biden has a chance of winning Iowa. Put it this way: Everything you used to think about Bill Richardson's chances you may soon be thinking about Joe Biden's chances instead... --Noam Scheiber