It would have been unimaginable even a couple of years ago. The most powerful Republican in Washington flew to San Diego this month to help raise money for an openly gay candidate for the House.

House Speaker John Boehner, R-Ohio, wasn’t just trying to help elect a Republican. He was trying to help his party build a new image, and reach out to voters it had spent the last decade shunning. His decision to campaign for gay candidates was met with surprisingly nominal opposition, which he was able to brush aside quickly.

Little-noticed and making barely a stir, Boehner’s trip was a potent sign of a fundamental shift in the country and its politics.

After decades of solid opposition, a majority of Americans now support marriage between those of the same sex, would accept it if a child of theirs were gay and say it wouldn’t make a difference if a candidate for Congress were gay. The shift has come rapidly; it was just in 2013 that a majority first supported same sex marriage.

This change didn’t come from political leaders. Rather, it was driven by Americans themselves, a “rainbow revolution” propelled by a new generation coming of age in a new era with new attitudes, older people becoming more familiar with gays and lesbians in their families and communities, workplaces that welcome gays, changing messages in popular culture and new conversations in places of worship.

As people are changing their attitude, politics is changing in reaction.

Democrats who long opposed same-sex marriage – such as Barack Obama and Bill and Hillary Clinton – all have changed their position. Many Republicans as well have changed, some in their position, some in their approach.

The state Republican Party in Nevada dropped its opposition to same-sex marriage. Tea party icon Michele Bachmann said marriage wasn’t even an issue this election.

And just a decade after opposition to gay marriage helped Republican George W. Bush win re-election, his political guru said he could envision one of his party’s presidential hopefuls in 2016 supporting same-sex marriage.

There are still opponents, to be sure. A solid segment of America opposes same-sex marriage. The Republican Party is torn. Some lawmakers are refusing to allow couples to marry, even as an avalanche of court rulings say they can. Religions such as the Roman Catholic Church weigh changes, then back off.

But rapidly changing views on gays and lesbians, particularly marriage, are altering politics this fall, perhaps for good.

Carla Jones, 59, a real estate agent from Orange County, California, is one who’s changed her mind. For her, it was realizing that sexual orientation is not a choice but rather something that a person is born with.

“We’re hard-wired, if you will, in our sexual preference,” she said. “Once I kind of understood that, then everything started to fall into place about same-sex marriage.”

The impact on politics is most evident in the Republican Party.

A Republican candidate for U.S. Senate is running statewide TV ads in favor of same-sex marriage. A pair of openly gay Republicans – Carl DeMaio of California and Richard Tisei of Massachusetts – are running in competitive House races, both featuring ads with their partners, both backed by Boehner. At least eight Republican members of Congress have indicated their support for same-sex marriage. Leading the pack: Sen. Rob Portman of Ohio, who reversed his longtime opposition because his son is gay.

Former first lady Laura Bush and former Vice President Dick Cheney support same-sex marriage. Former President George H.W. Bush and his wife, Barbara, served as official witnesses at the wedding of two women in September 2013.

The shifting politics were reflected more broadly, and quickly, in the Democratic Party.

For years, Democratic leaders opposed same-sex marriage. But they, too, moved in the wake of public opinion.

Obama opposed same-sex marriage through his 2008 election, then said his thinking was evolving. In 2012, he changed his mind. He said he was influenced by his wife and young daughters.

Bill Clinton, who signed a 1996 law allowing states to refuse to recognize same-sex marriages that had taken place in other states, argued for its repeal last year.

Unlike previous years, gay and lesbian issues, including same-sex marriage, have garnered little attention in elections this fall, even in the races where gay candidates are running.

In Maine, for example, where Democrat Mike Michaud could become the first openly gay governor in the nation, the central issue is his rival’s leadership style, not his own lifestyle.

“Yes, I am gay,” Michaud wrote in a guest column in the Bangor Daily News last November in response to rumors about his sexual orientation. “But why should it matter?”

“This cycle could make an end to identity politics,” said Gregory T. Angelo, the executive director of the Log Cabin Republicans, which calls itself the nation’s largest Republican organization advocating for equal rights for gays and lesbians.

Eighty-three percent of adults said that whether someone was gay wouldn’t make a difference in whether they voted for that candidate, according to a recent McClatchy-Marist poll. That’s nearly double the 49 percent who felt that way when the Los Angeles Times asked them in 1985.

This may not yet change the internal workings of the Republican Party when it comes to primary contests. Polls find that Republicans still oppose same-sex marriage by more than 2-to-1. Tea party supporters oppose it by nearly 3-to-1.

But it’s affecting general elections, in which candidates have to face voters who are in the middle.

John Feehery, a Republican political consultant and former congressional aide, said same-sex marriage wasn’t a “particularly good general election issue” for his party. “Republicans are trying to figure out how to expand the party,” he said.

Bachmann, the Republican congresswoman from Minnesota who’s lobbied against same-sex marriage for years, told reporters at the recent Values Voter Summit in Washington that same-sex marriage isn’t an issue in this year’s elections. “In fact, it’s boring,” she said.

Republican consultant Karl Rove, who watched anti-same-sex-marriage amendments in 11 states boost turnout that also helped President George W. Bush in 2004, now says he can imagine a 2016 presidential hopeful from his party supporting same-sex marriage.

This shift isn’t universal, however, as a large slice of America still opposes same-sex marriage.