The drive to legalize same-sex marriage in Minnesota has received a boost, as a Republican state senator prepares to cross party lines and join the effort.

"At this point, I am concerned about doing the right thing," state Sen. Branden Petersen (R) told the Minneapolis Star Tribune. "I have a certain amount of peace about that, and I will let the chips fall where they may."

If Petersen signs on to the same-sex marriage bill expected to be introduced this week, he would be the first Republican lawmaker to do so. His cosponsorship would be especially significant because he was among a majority of GOP legislators who put a constitutional amendment on the November 2012 ballot that would have banned marriage equality in Minnesota. Voters defeated the measure.

Petersen's father-in-law has been in a same-sex relationship for nearly 20 years and he says the issue has divided his family.

"It's only a matter of time before same-sex marriage is legal," Petersen said. "I thought it was important to engage the issue now, and when we do it, do it right, and that there's some perspective from the people I represent in that."

Petersen said that before he signs on as a co-sponsor, he wants to make sure that religious leaders are not forced to wed same-sex couples if doing so would be against their beliefs, and to ensure that children with same-sex parents who divorce receive the same financial guarantees as children with heterosexual parents.

According to the Minneapolis Star Tribune, state Sen. Scott Dibble (DFL), who is the lead sponsor of the bill and gay, said he has "no problem" with Petersen's suggestions and is excited to have him on board.

"It's awesome," he said. "I think it also allows a lot of space for other legislators to consider the same."

A recent survey by Public Policy Polling found that 47 percent of Minnesotans support marriage equality, compared to 45 percent who oppose. Seventy-five percent back civil unions.

Gov. Mark Dayton (DFL) has pledged to sign marriage equality legislation if it reaches his desk.

On the national level, the Respect for Marriage Coalition launched a $1 million ad campaign Wednesday advocating for the legalization of same-sex marriage. The effort highlights the bipartisan support for the issue, with clips of President Barack Obama, former Vice President Dick Cheney, former First Lady Laura Bush and former Secretary of State Colin Powell speaking out in favor of marriage equality.

Clarification: A previous headline elsewhere on the site omitted to say that Petersen is the first GOP lawmaker in Minnesota to endorse the legislation.

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  • Connecticut

    Since November 12, 2008

  • Delaware

    Gay marriage law <a href="" target="_blank">enacted</a>, weddings to begin July 1.

  • Iowa

    Since April 3, 2009

  • Maine

    In 2012, Maine voted in favor of a ballot amendment to legalize gay marriage.

  • Maryland

    The gay marriage bill was signed into law by Gov. Martin O'Malley (D) on March 1, 2012. Opponents later gathered enough signatures to force the issue back onto the ballot in November 2012, but voters rejected the effort against gay marriage.

  • Massachusetts

    Since May 17, 2004

  • Minnesota

    Same-sex marriage bill signed into law in May. Gay marriages will begin in August.

  • New Hampshire

    Since January 1, 2010

  • New York

    Since July 24, 2011

  • Rhode Island

    Bill passed in May. Law takes effect on August 1, 2013.

  • Vermont

    Since September 1, 2009

  • Washington

    On February 13, 2012, Gov. Christine Gregoire (D) signed a law allowing same-sex marriage ceremonies to begin on June 7, 2012. The process was delayed by gay marriage opponents who gathered enough signatures to put the issue up to a state vote in November 2012. They voted to approve it on Election Day.

  • Washington D.C.

    Since March 9, 2010

  • California

    The state initially began conducting gay marriages on June 16, 2008. On November 5, 2008, however, California voters passed Proposition 8, which amended the state's constitution to declare marriage as only between a man and a woman. In 2013, the Supreme Court ruled against that law, and the state shortly thereafter began sanctioning same-sex nuptials.