Romney’s four-point edge over Obama in likely voters’ preferences for president contrasts with Obama’s seven-point win over McCain in the 2008 election. To gain an understanding of the underlying dynamics of this shift, the following analysis contrasts the Obama versus McCain margins across major subgroups in 2008 with the Obama versus Romney margins in the full week of Gallup interviewing conducted Oct. 9-15. This shows that compared with 2008, Obama’s support is down the most among voters in the South, 30- to 49-year-olds, those with four-year college degrees, postgraduates, men, and Protestants. He has also slipped modestly among whites, Easterners, women, and Catholics.

Obama’s support is roughly the same now as in 2008 among 18- to 29-year-olds, seniors, nonwhites, and voters in the West and Midwest; however, he has not gained support among any major group compared with 2008.

In order to compare Obama’s support today with 2008, the data in the graph below for both 2008 and 2012 are re-percentaged on the basis of support for the Democratic and Republican candidates only, excluding “no opinion” responses and support for minor third-party candidates. The 2008 results reflect an additional adjustment to align Gallup’s final likely voter result with the election outcome.

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