Michigan polls show Romney gained after GOP debate

Two new polls in the showdown state of Michigan suggest that Rick Santorum failed to gain a badly needed shot of momentum in Wednesday night’s Republican presidential debate.

The opinion surveys reflect a race that still remains close in a must-win state for Mitt Romney. The Michigan native holds a three-point edge over Santorum in one poll and a slightly more comfortable six-point advantage in the other.

Romney arrived in Michigan on Thursday evening and plans to campaign around the state every day through Tuesday’s primary. Santorum has stops planned in the vote-rich Detroit metro area on Friday evening and Saturday morning, and he’s due to return on Monday.

An overnight poll by Mitchell Research and Communications, a Republican firm in East Lansing, found that one-third of Michigan primary voters surveyed thought that Romney won the nationally televised debate, versus 13% who thought Santorum won. Another 10% named Ron Paul as the debate winner, and 9% picked Newt Gingrich (for those trailing candidates, the figures roughly reflected their overall support among GOP primary voters in the state).

The debate caused nearly one in 10 Michiganders to switch their support, according to the poll of 430 likely primary voters conducted Thursday night. Among the switchers, 27% moved to Romney and 22% to Santorum, which helped Romney add one point to his statistically insignificant lead in a survey by the same pollster four nights earlier.

A new Rasmussen poll, which also surveyed likely Michigan primary voters on Thursday night, showed a much more dramatic shift. It showed Romney pulling away from Santorum, by 40% to 34%. Just three days earlier, the same pollster had Santorum up by a 38-34 margin.

Far back in the state are Paul at 10% and Gingrich at 9%. Paul will campaign in Michigan this weekend, while Gingrich is skipping the state.

Both of the post-debate polls showed that Santorum lost ground significantly among supporters of the tea party movement, who may have been turned off by his confession in the debate that his Senate votes sometimes betrayed his conservative convictions.

Rasmussen’s survey of 750 likely Republican primary voters had a margin of sampling error of 4 percentage points. Both of the new Michigan surveys were automated polls, as opposed to those which use live operators and are considered more reliable; however, automated polls can provide a valuable glimpse into trends in opinion, which in Michigan, at least appear to be moving Romney’s way.

paul.west@latimes.com