Bachmentum? Michele Bachmann’s momentum continues in her birth state of Iowa, according to a new poll of likely caucus voters by the Iowa Republican.  Bachmann surpasses Mitt Romney by four points, while another Minnesotan has also muscled up the ranks:

Minnesota Congresswoman Michele Bachmann has surpassed former Massachusetts Governor Mitt Romney in a recent Iowa poll that was conducted by TheIowaRepublican.com.  With Bachmann now leading in Iowa, Romney has fallen to second place, but he is still well ahead of third place finisher Tim Pawlenty, who has overtaken Herman Cain my a miniscule margin.

Bachmann received support from 25 percent of likely Iowa caucus goers in the poll, while Romney is backed by 21 percent.  The poll also shows signs of growth for former Minnesota Governor Tim Pawlenty, who now stands in third place in statistical tie with Herman Cain at just under nine percent.  Ron Paul finished with six percent, Newt Gingrich with four percent, Rick Santorum with two percent, and Jon Huntsman rounded out the field with one percent. …

While Bachmann’s lead over Romney is just within the margin of error, the poll’s cross tabs show how much momentum her campaign has generated in Iowa.  Her favorability is ten points higher than Romney’s, who had the second highest number in that category.  Her unfavorable figure is 14 points lower than Romney’s, giving her a stellar plus 65 favorability margin.  Her numbers suggest that Bachmann has found a very effective way to appeal to caucus goers.

The candidate with the next highest favorable/unfavorable spread is Tim Pawlenty with a plus 48 margin.  Like Bachmann, Pawlenty is well liked by caucus goers, but he has found it more difficult to move his overall polling number in the state.  Pawlenty finished in third place in the poll by edgeing out Herman Cain, 8.8 percent to 8.5 percent.  Pawlenty’s numbers have increased since the Des Moines Register poll showed him at 6 percent.  A major factor could be the radio and television ads the Pawlenty campaign has been airing in the past few weeks.

Romney’s decline shouldn’t surprise too many people.  He pulled out of the Ames poll next month, which is both an early test of the field and a fundraising opportunity for the state GOP.  It’s not exactly shocking that enthusiastic Republican caucus goes might have gotten a little less enthusiastic about Romney after his withdrawal.  I would expect a finish for Romney in Ames — and likely in January’s real caucus — at third or less.

Bachmann has to score well in Iowa and in the Ames poll to keep the media spotlight and political momentum.  So does Pawlenty, who has gotten more aggressive in the state.  His standing increased a little in this survey, barely edging out Herman Cain for third place, but he’s going in the right direction. Pawlenty needs a second place finish in January at a minimum to keep his presidential campaign viable, as New Hampshire will almost certainly belong to Romney.  He has another four weeks until the Ames debate and straw poll to establish himself in his own backyard.

Still, the big questions for Bachmann and Pawlenty remain these: Sarah Palin and/or Rick Perry.  If either or both get in the race before Ames, they could find themselves swamped out of the spotlight and the enthusiasm of caucus-goers.

Andrew Malcolm looks at the new numbers as well.