Reuters poll over-samples Democrats by 9 percent, finds 7-point Obama edge

A Reuters poll released Tuesday bucked recent trends and showed President Barack Obama ahead of former Massachusetts Gov. Mitt Romney by seven points. The poll, however, appears to have over-sampled Democrats by a wide margin, skewing the results in the president’s favor.

Though a January Gallup poll found that Democrats outnumber Republicans in the United States by only 4 percent, an April Rasmussen poll showed a 35.1 percent to 33.1 percent split in favor of self-identified Republicans. (RELATED: Full coverage of the 2012 elections)

Still, the Americans¬†polled by Reuters were 47 percent Democrats, 38 percent Republicans and 15 percent independents — a nine-point difference in favor of voters likely to support President Obama’s re-election effort.

The Reuters poll was conducted between May 3 and May 7. Three other polls — by Rasmussen, Gallup and Politco/GWU/Battleground — conducted at a similar time show Romney winning by five points, three points and one point respectively. An IDB/CSM/TIPP poll showed Obama ahead by three, and a poll by the Democratic-affiliated Democracy Corps showed the two candidates tied.

A spread compiled by Real Clear Politics averaging those six polls put Obama ahead by .2 points. But with the Reuters poll a clear outlier, it’s likely that Romney would hold a slight edge if polling samples more closely reflected the leanings of likely voters.

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