In Florida, 54 percent of voters believe gay marriage should be legal, while 33 percent think it should be illegal. In Ohio, 52 percent say it should be legal, while 37 percent say it should be illegal.

In 2004, by contrast, nearly two-thirds of Ohio voters -- 62 percent -- supported a constitutional amendment defining marriage as "only a union between one man and one woman." The Ohio ballot initiative may have driven more voters to the polls who then supported Bush, according to exit polls.

In 2006, 57 percent of Virginia voters supported similar legislation. And in 2008, among Florida voters, 62 percent supported an amendment limiting gay marriage in their state.