"The findings by the nonpartisan Pew center show Americans taking a pro-abortion position by a 54-40 percentage point margin in 2007 and 2008.
Now, two surveys of 5,500 adults found 47 percent support legal abortions with 44 percent opposed.
The old 14 percent advantage for the pro-abortion side has dropped to three percent -- very near the margin of error.
"Now ... there have been modest increases in the numbers who favor reducing abortions or making them harder to obtain," the polling firm said. "The pattern of changes suggests that the election of a pro-choice Democrat for president may be a contributing factor."
One of the largest declines in support for legal abortion has occurred among white, non-Hispanic Catholics who attend Mass at least weekly. Substantial change has also occurred among Democratic men (with support for legal abortion down nine points) but not among Democratic women.
Pew also found that pro-life advocates have an intensity factor in their favor.
While only eight percent of liberal Democrats view abortion as a critical issue, 26 percent of conservative Republicans call abortion a critical issue.
There has been a 26-point drop since 2006 in the proportion of liberal Democrats who say abortion is a critical issue, from 34% to 8%. But among conservative Republicans, the decline has been much smaller (nine points, from 35% to 26%).
This shift in attitudes is also evident on other measures of public opinion about limits on abortion.
Some 41 percent now say they favor making it more difficult to obtain an abortion, up six points from 35% in 2007. In 2005, 59% of respondents agreed it would be good to reduce abortions. Today 65% take this view, an increase of six points.
And three-quarters (76%) continue to favor requiring minors to obtain the permission of a parent before having an abortion.
The Pew poll also found fewer Americans, and fewer pro-life advocates are willing to compromise on abortion by finding some "middle ground.""
"PRINCETON, NJ -- A new Gallup Poll, conducted May 7-10, finds 51% of Americans calling themselves "pro-life" on the issue of abortion and 42% "pro-choice." This is the first time a majority of U.S. adults have identified themselves as pro-life since Gallup began asking this question in 1995.
The new results, obtained from Gallup's annual Values and Beliefs survey, represent a significant shift from a year ago, when 50% were pro-choice and 44% pro-life. Prior to now, the highest percentage identifying as pro-life was 46%, in both August 2001 and May 2002."