The apparent shift, which contradicts some other recent polls, appears in a poll by the Pew Research Center released on Thursday. A 2008 poll by Pew researchers had found that those in favor of keeping abortion legal outnumbered opponents, 54 percent to 40 percent. In the new Pew poll, the gap has narrowed: 47 percent of those surveyed said abortion should be legal in all or most cases, and 45 percent said it should be illegal in all or most cases — a difference within the poll’s margin of sampling error.
The new survey did not find the reasons for the shift in opinion. But Pew researchers pointed out that the shift has occurred since the election of President Obama, a Democrat who supports abortion rights but has often spoken about the need to reduce the number of abortions.