Some top aides argued that gay marriage is toxic at the ballot box in battleground states like North Carolina and Virginia because, as Tuesday's vote proved, the issue remains a reliable way to fire up rank-and-file Republicans. It also could open Obama up to Republican criticism that he was taking his eye off the economy, voters' No. 1 issue.
Other Democratic supporters claim Obama could energize huge swathes of the party, including young people, by voicing his support for gay marriage before November. He also could appeal to independent voters, many of whom back gay marriage, and he could create an area of clear contrast between himself and his Republican rival as he argues that he's delivered on the change he promised four years ago.
On Tuesday, former Pennsylvania Gov. Ed Rendell, a Democrat, told Obama to “man up” and take a position on gay marriage.
Romney has not generally raised the issue in his campaign.
On Wednesday, he told KDVR-TV in Denver that “I do not favor marriage between people of the same gender, and I do not favor civil unions if they are identical to marriage other than by name. My view is the domestic partnership benefits, hospital visitation rights, and the like are appropriate but that the others are not.”
The Romney campaign did not respond to questions about which benefits the Republican candidate would oppose.
The former Massachusetts governor told an Ohio television station Monday that he believes “marriage is between a man and a woman, and that's a position I've had for some time and I don't intend to make any adjustments at this point — or ever, by the way.”
Public opinion on gay marriage has shifted in recent years, with most polls now finding the public evenly split, rather than opposed.
A Gallup poll released this week found 50 percent of all adults in favor of legal recognition of same-sex marriages, marking the second time that poll has found support for legal gay marriage at 50 percent or higher. Majorities of Democrats (65 percent) and independents (57 percent) supported such recognition, while most Republicans (74 percent) said same sex marriages should not be legal.
Six states — all in the Northeast except Iowa — and the District of Columbia allow same sex marriages. In addition, two other states have laws that are not yet in effect and may be subject to referendums.
AP Deputy Director of Polling Jennifer Agiesta and Philip Elliott in Colorado contributed to this report.