Arizona has been a disappointment to anti-gay marriage activists since 2006, when the state became the first in the nation to reject a ballot measure banning same-sex marriage.

Those same opponents are hoping for redemption Tuesday, when Arizona voters again will have to decide whether they want the state's constitution to be amended to define marriage as a union between one man and one woman.

"It actually helped us out having it fail the first time because it allowed us to raise more money," said state Sen. Ron Gould, a Republican and prime sponsor of this year's measure, which was put on the ballot by the Legislature. "It just motivates people to put the remote down, get out of the La-Z-Boy and do something."

Twenty-seven states have approved anti-gay marriage ballot measures, including seven in 2006. Similar measures are being considered in California and Florida this year.

Although Arizona voters turned down the 2006 measure, there is a big difference between that one and this year's measure, Proposition 102.