By Sarah N. Lynch
WASHINGTON (Reuters) - Ohio Republican Senator Rob Portman, who was on the short list last year to be the party's vice presidential candidate, has reversed his opposition to same-sex marriage after learning in 2011 that his son is gay.
In a newspaper opinion piece Friday that comes in the wake of recent advances for gay rights, Portman said he now supports gay marriage. He is believed to be the only sitting Republican senator to back gay marriage.
"I have come to believe that if two people are prepared to make a lifetime commitment to love and care for each other in good times and in bad, the government shouldn't deny them the opportunity to get married," Portman wrote in an op-ed piece in Ohio's Columbus Dispatch paper, titled "The Freedom to Marry."
"That isn't how I've always felt. As a Congressman, and more recently as a Senator, I opposed marriage for same-sex couples. Then, something happened that led me to think through my position in a much deeper way."
Portman's 21-year-old son, Will, told the senator and his wife that he was gay in February 2011, and had been "since he could remember."
It was the latest show of public support for gay rights. President Barack Obama announced last year that he approved of gay marriage, and in his inaugural speech in January, he equated gay rights with civil rights.
How the Supreme Court deals with two cases this year will be a test of how far the momentum has swung in favor of gay marriage.
The court hears oral arguments later this month in two cases related to gay marriage. One challenges the 1996 federal Defense of Marriage Act, which defines marriage as a union between a man and a woman. In a related case, the court will also hear arguments that question a California law, known as Proposition 8, banning gay marriage.
More than two dozen Republicans added their names to a legal brief urging the Supreme Court to reject Proposition 8. They include former presidential candidate, Jon Huntsman, and former candidate for California governor, Meg Whitman.
Portman told the Cleveland Plain Dealer newspaper he now believes same-sex couples who marry in states where it is legal should be eligible for the same federal benefits granted to heterosexual couples.
Portman served as trade representative and then White House budget director under former President George W. Bush.
He was among the front-runners to be Mitt Romney's vice presidential pick during the 2012 election, but budget hawk Representative Paul Ryan of Wisconsin eventually got the nod.
The Republican Party has become increasingly split on the gay marriage issue, with many arguing that socially conservative positions such as opposition to same-sex marriage are contributing to the party's election losses.
An early Republican favorite for the 2016 presidential race, Senator Marco Rubio of Florida, staged a defense of traditional marriage in a high-profile speech to a conservative conference on Thursday.
"Just because I believe that states should have the right to define marriage in the traditional way does not make me a bigot," the 41-year-old Cuban-American told the Conservative Political Action Conference.
Portman's new position was supported by former opponent David Axelrod, who was Obama's senior campaign advisor.
"Courageous decision by Rob Portman to endorse same-sex marriage, guided by the love of a parent rather than by party ideology," Axelrod tweeted.
In his op-ed piece, Portman wrote of how he has "wrestled" with reconciling his Christian faith with the desire for his son to have the same opportunities as his siblings.
"Ultimately, for me, it came down to the Bible's overarching themes of love and compassion and my belief that we are all children of God," he said.
The senator said his views on the matter evolved over the past two years, and he had consulted clergy members and friends including former Vice President Dick Cheney. Cheney, who has an openly gay daughter, has reiterated his support for gay marriage over the past several years, despite his deeply conservative views on many issues.
Bob Vander Plaats, president of the Family Leader, an influential group of social conservatives in Iowa, said Portman had been "short-sighted" for changing his views.
"I don't see the Republican Party any time soon abandoning his stance on marriage. I see more than anything it is emboldened in their stance on marriage," he said. "The last time I checked, God's word was the same yesterday, today, and tomorrow," he said.
(Additional reporting by Alistair Bell and Samuel P. Jacobs; Editing by Vicki Allen and Bernadette Baum)
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