Back in December, Quinnipiac found that, by a small margin, more Ohioans opposed same-sex marriage than favored it—the margin was 47 percent to 45. But now a new poll by Quinnipiac finds the political landscape has flipped in Ohio: 48 percent of voters say they back the legalization of same-sex marriage and 44 percent are opposed.

The poll shows gay rights activists have come a long way since 2004, when more than 60 percent of Ohioans voted for a constitutional amendment banning same-sex marriage.

Now some gay rights activists are now collecting signatures on petitions to put a new proposal onto the ballot that would legalize gay marriage in Ohio.

One counterpoint in this new Quinnipiac poll: U.S. Sen. Rob Portman has lost popularity among Ohio voters since his recent endorsement of marriage equality.

Two months ago, the percentage of Ohioans approving his performance outnumbered the percent disapproving by 20 points— now that’s down to nine. The poll finds that’s because many Republicans are upset the G.O.P. senator switched from a same-sex marriage opponent to a supporter.