Gerald Herbert, Associated Press
Republican presidential candidate, former Massachusetts Gov. Mitt Romney greets supporters at a campaign rally in Kentwood, Mich., Wednesday, Feb. 15, 2012.

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Mitt Romney's positive intensity in the Gallup tracking survey jumped among Republicans in the past month, even as it fell among Democrats, new polls show. The score subtracts those who strongly disfavor a candidate from those who strongly support him. Both positive and negative intensity are seen as a key indicator of voter turnout.

President Obama's intensity remained static during that same period, but he remains more polarizing than Romney. While Romney stands at +21 among Republicans and GOP-friendly independents, and at -30 among Democrats and Democrat-leaning independents, Obama rates -47 and +36.

Gallup admits it is not totally sure what its intensity measure will prove. This is the first year they have tracked it. "It is certainly possible for people holding strong views of one candidate or the other to be more motivated to vote, to officially register their support for or opposition to the candidate. So the candidates' scores could indicate their overall strength as well as whether voters are inclined to turn out to support them or to oppose their opponent," the Gallup website stated.

Rusmussen Reports also measures the intensity of presidential job approval, also on the theory that intensity shapes turnout. The Rasmussen survey currently shows that 23 percent strongly approve of Barack Obama's performance, while 41 percent strongly disapprove, for a -18 intensity index.

There are two differences between the two polls, however. Gallup polls all registered voters, while Rasmussen filters for likely voters. Gallup is asking about personal favorability on their intensity scale, while Rasmussen is focused on presidential job approval.

Likely voter surveys will filter out some Obama supporters, including youth and minorities who in the pollster's best estimate are less likely to vote. Favorability ratings for Obama are much higher than job approval ratings, and the latter, experts say, are more likely to predict the vote.

At the National Journal website on Tuesday, Charlie Cook offers a peek at the shape and meaning of voter intensity. He describes a focus group he attended of GOP voters and GOP-leaning independents. After a two-hour dialogue, he concluded that these voters would support Romney, but not because they were "personally bonded" to him. Rather, they were mostly poised to vote against Obama.

"It wasn’t so much that they didn’t like Romney. They clearly felt that they didn’t know him, and that he owes his front-runner status more to his opponents’ shortcomings and to ads by and for Romney attacking his rivals. These voters said they didn’t have enough information to support him outright. The lack of a personal connection to Romney was striking," Cook wrote.

The theory of the intensity polls is that if Romney could establish a stronger bond with GOP voters while downlplaying hostile motivation among Democrats, the balance of turnout in November could tip in his favor.

Eric Schulzke writes on national politics for the Deseret News. He can be contacted at [email protected].