"We must change the Wisconsin State Constitution to say that marriage is to be between one man and one woman," Walker said in November 2005 during a brief run for governor that year. "My belief in this position is even stronger today."
Walker said he voted for the ban, joining with 59 percent of voters statewide to add the ban to the state constitution in 2006. He had previously voted as a member of the state Assembly for a bill in 1997 to prohibit same-sex marriages and declare those conducted in other states to be invalid.
As Milwaukee County executive in 2009, Walker vetoed a measure to provide benefits to same-sex partners of county workers. And once elected governor, in 2011, he fired the state's attorney defending Wisconsin's domestic registry law. The state Supreme Court is currently weighing whether the registry violates the state ban on gay marriage.
But in May, Walker has said he doesn't think it will be an issue in this year's governor's race.
"Voters don't talk to me about that," Walker said then, sidestepping questions about whether he still personally supported the ban. "They talk to me about the economy, they talk to me about their kids' schools, they talk to me about making sure we keep our finances in order."
Walker's reluctance to stick to his hard-line position may be explained by recent polls showing growing public support for same-sex marriages.
A Marquette University law school poll released in May found that 55 percent of registered Wisconsin voters favor allowing gays and lesbians to marry legally. That was up from 44 percent in October 2012.
Walker's likely Democratic opponent in this year's race for governor, Mary Burke, supports legalizing same-sex marriage and said she voted against the 2006 constitutional ban.
"Finally recognizing that committed, loving Wisconsin couples have the freedom to marry whomever they choose represents an important step forward for our state," Burke said in a statement Thursday. "From strengthening our communities to making our state more competitive economically marriage equality makes Wisconsin stronger."
The American Civil Liberties Union sued over the ban in February on behalf of eight same-sex couples. U.S. District Judge Barbara Crabb last week struck down the ban as unconstitutional, but did not give direction to state officials about what to do.
A majority of county clerks around the state have issued marriage licenses to same-sex couples, even as Republican Attorney General J.B. Van Hollen continues to ask both Crabb and a federal appeals court to put the decision on hold while he appeals the case.
Both Republican and Democratic clerks, in both Republican and Democratic-voting counties, are issuing the licenses. Around 500 licenses had been issued statewide in less than a week.
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