[marriage12-art0-gvsukc72-1fiscal-summit-jpeg-08a75.jpg?__scale=w:660,h:440,t:1,c:ffffff,q:80,r:1] View Slideshow Request to buy this photoAP file photo Sen. Rob Portman, R-Ohio, favors gay marriage, but that position could hurt him in the early primaries if he runs for president in 2016.

WASHINGTON — The reaction would have been very different 10 years ago: Had the U.S. Supreme Court struck down bans on same-sex marriage in any state in 2004, conservative Republicans would have howled in protest.

But this week, when the justices upheld lower-court rulings that essentially legalized same-sex marriage in five states, a sizable number of Republicans seemed to shrug off the news as no big deal.

The relatively quiet GOP response — House Speaker John Boehner of West Chester never even commented on it — is a sign that a divisive issue across the country a decade ago has become acceptable to many Americans.

A Pew Research Center survey last month showed that 49 percent of Americans favor same-sex marriage, while 41 percent oppose it. A Pew poll from 2004 showed that, at the time, 60 percent of Americans opposed gay marriage, while 31 percent supported it.

Ten years after voters in Ohio approved a constitutional amendment banning same-sex marriage, 62 percent to 38 percent, half of the states and the District of Columbia permit same-sex marriage. A Washington Post poll last year showed that 81 percent of people younger than 30 support same-sex marriage.

“Nothing has changed quicker in the political environment than the politics surrounding gay marriage,” said David Leland, former chairman of the Ohio Democratic Party and a candidate this year for the Ohio House. “There has been a sea change of enormous proportions in the past 10 years. I think the silence from the Republicans is reflective of that.”

Analysts say that as the issue fades, it will be less of an obstacle for potential Republican presidential candidates such as Sen. Rob Portman of Ohio who favor same-sex marriage. Portman announced last year that his son Will is gay and reversed his longtime opposition to same-sex marriage.

Portman was the first sitting GOP senator to publicly support gay marriage. Barry Bennett, a Republican consultant in Washington and a Portman adviser, said Portman’s position would “ absolutely” help him if he could win the GOP nomination.
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“Our problems in the general are primarily driven by voters seeing us as not caring and not compassionate,” Bennett said. “They won’t see Rob that way.”

Yet Portman’s stance is fraught with political danger. Politico.com reported this week that only four House Republicans and four Senate Republicans support same-sex marriage. Republicans might not want to talk about same-sex marriage, but they are not embracing it, either.

The Pew poll shows that only 34 percent of Republicans back same-sex marriage and that 75 percent of white evangelicals — who make up a strong segment of GOP voters in the early presidential contests of Iowa and South Carolina — oppose gay marriage.

“He’ll never get through the primary,” Mary Anne Marsh, a Democratic consultant in Boston, said of Portman. “While Portman, on paper, could be a good general-election candidate , the people who dominate the Republican primary process oppose gay marriage. Period.”
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Phil Burress, president of Citizens for Community Values in Ohio, said, “There’s no way that it has helped him, and it continues to hurt him. He’s damaged goods.” He predicted that Portman is “ not even going to keep his seat in 2016.”

In a statement, Portman said he backs “same-sex marriage and the Supreme Court’s ruling opens up the possibility of marriage to more Americans.” But Portman said that “the best way to achieve enduring change is at the kitchen table, not in the courtroom. It is citizens persuading their fellow citizens, and it is happening all across the country.”

While Portman was one of the few Republicans to praise the court’s ruling, most GOP officials said nothing, suggesting they hoped to avoid a blistering controversy before the November congressional elections.
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But some were not so reticent. Sen. Ted Cruz, R-Texas, assailed the court’s decisions as “both tragic and indefensible,” and he vowed to introduce a constitutional amendment “to prevent the federal government or the courts from attacking or striking down state marriage laws.”

Cruz is likely to run for president, and his opposition to same-sex marriage would resonate with social conservatives who make up a large percentage of Republicans voting in the 2016 Iowa caucuses.

In 2012, former Pennsylvania Sen. Rick Santorum, an ardent opponent of abortion rights and same-sex marriage, won Iowa with 25 percent of the vote, while in 2008, former Arkansas Gov. Mike Huckabee — another social conservative — won with 34 percent.

But those close to Portman point out that neither Santorum nor Huckabee were able to win the nomination. They suggest that a number of GOP voters in Iowa might overlook a candidate’s position on same-sex marriage.

“There are still a huge chunk of people who are caucus voters who will agree with Portman on this,” said one Republican who spoke on condition of anonymity. “I don’t think the gay marriage thing was a deal-breaker anyway. With the passing of time, it’s becoming less and less of an issue."

As recently as 2004, opposition to same-sex marriage might have helped President George W. Bush win Ohio, whose electoral votes gave him a second term. Bush carried the state on the same day that voters approved an amendment to the Ohio constitution banning same-sex marriage.

“It was the factor,” Burress said in explaining why Bush won.