It is a theme that has become increasingly familiar during the rapid evolution of American political attitudes toward same-sex marriage: People who learn that a friend or loved one is gay are far more likely to support same-sex marriage, even if they were once adamantly opposed.
Ohio Sen. Rob Portman, who became the first Republican in the U.S. Senate to openly endorse same-sex marriage, is simply the latest.
Portman, in an op-ed published Friday in Ohio's Columbus Dispatch, said his turnabout was prompted after his son, Will, revealed two years ago that he is gay.
The switch, coming less than two weeks before the U.S. Supreme Court hears a pair of challenges to same-sex marriage bans — including one that Portman voted for — is being characterized by gay rights activists and others as historic.
This feels like the point, they say, at which Republican-led opposition to gay marriage may have begun its most public, perceptible erosion.
"Portman is politically conservative, but he's never come across as an ideologue," said Kyle Kondik, a political analyst and former Ohioan who characterized the senator, a former Bush administration budget official who was on Mitt Romney's short list for vice president, as "an insider politician."
"This is probably just the tip of the spear; we're going to see more of this," said Kondik, at the University of Virginia's Center for Politics. "He's the first Republican senator who supports gay marriage, and he certainly won't be the last."
Former GOP Vice President Dick Cheney, whose daughter is a married lesbian, has long supported same-sex marriage, and provided counsel to Portman. Prominent Republicans, most of them not in elected office, filed a brief urging the Supreme Court to overturn bans on same-sex marriage.
And one of the cases seeking marriage equality is being argued by Theodore Olson, a U.S. solicitor general during the George W. Bush administration.
Hero Or Hypocrite?
It seemed to matter little to marriage equality supporters that it took a personal connection for Portman to switch his views just three years after being elected to the Senate (although the comments section in the Columbus Dispatch was filled with readers alternately dinging Portman for failing to have empathy for gay Americans before his son came out, excoriating him for his switch up, and lauding him for his same-sex marriage journey).
"This is our moment," said Gregory Angelo, president of the Log Cabin Republicans, the national gay and lesbian GOP organization. "We've been working toward this for over 30 years."
"Sen. Portman's recent evolution on this issue underscores that it is possible to be a conservative who is supportive of marriage equality," Angelo said. "It is possible to be a committed and practicing Christian who is supportive of marriage equality."
"There is," he said, "a conservative case to be made for the freedom to marry."
At Marriage Equality, the national group working to secure same-sex marriage in the States, Stuart Gaffney characterized Portman's announcement as "pitch perfect."
"His was the true articulation of family values," Gaffney said. "He loves his son, just as he loves all his children, and believes all should have a right to marry."
Nine states and the District of Columbia have legalized same-sex marriage; 10 states have extended to gay couples some marriagelike benefits; 31 states, including Ohio in 2004, have defined marriage as between a man and a woman.
That Portman's announcement came just before the Supreme Court arguments on challenges to California's state ban on same-sex marriage, and the federal law defining marriage as between a man and a woman, was seen by activists on both sides as intentional.
"The court is always supposed to maintain objectivity, but they don't live in a bubble, they're not in isolation chambers," said Angelo, of the Log Cabin Republicans. "Everyone on the Supreme Court is going to be aware of this news."
Portman's move, and his timing, angered those, like Brian Brown of the National Organization for Marriage, who have been working to stop efforts to legalize same-sex marriage.
Brown said he believes that Portman coordinated his announcement with same-sex marriage supporters.
"There is a concerted effort to pick off Republicans and make us appear divided," he said, arguing that same-sex marriage efforts have only succeeded in "deep blue states that Republicans have not won statewide in forever."
He dismissed polls showing growing support for marriage equality as "not worth the paper they're written on."
"He's going to be held accountable by the voters of Ohio," said Brown, who was attending the annual Conservative Political Action Conference outside Washington. "The issue of his son going out as gay is not a public policy decision."
Over his 14 years in Congress, the bulk of it in the House, Portman has been given an 87 percent lifetime rating by the American Conservative Union, sponsor of CPAC. The group's average rating for Senate Republicans was 77.83 in 2012; Portman was rated at 76 percent.
Portman was elected in 2010 with 56.8 percent of the vote on a platform that included opposition to same-sex marriage, Brown said, and "he will be held accountable in a primary in Ohio."
"Social conservatives," Brown said, "are not going to be kicked to the corner."
But Portman is not up for re-election until 2016. "In the life history of this issue, that's a long time," said The University of Akron's John Green, an expert on religion and politics.
Iowa social conservative Bob Vander Plaats, who also was attending CPAC, told NPR that while he sympathizes with Portman as a father, he doesn't agree with his stance.
"As a dad, I can definitely relate to him and his love for his son," Vander Plaats said, adding that if he had a gay son, it wouldn't change his love for him.
"It also would not change my view on God's design for marriage," he said. "Marriage is between one man and one woman."
Vander Plaats cited the anti-same-sex marriage views of the new Pope Francis.
Polls have consistently shown that a majority of U.S. Catholic voters support same-sex marriage.
In 2012, President Obama for the first time expressed his support for same-sex marriage, completing what he characterized as his evolution on the issue.
Green sees parallels in Portman's journey.
"I don't think Sen. Portman's situation is unique at all — a lot of elected officials have changed their view on same-sex marriage because of a friend or family member," he said. "We're all formed by our personal experience."
Something that was once ideological and abstract can become intensely personal. But Green, who has long known Portman, does not discount the political environment in which the senator made his decision.
"I don't think it's entirely coincidental that this comes as the issue is shifting in public opinion," Green said. "This is part of a broader political trend, even among Republicans."
And the political downside for Portman in Ohio is seen as negligible. "I can't imagine he would be vulnerable in a  primary," said Kondik, the former Ohioan. Challenger money from the big funders like Club for Growth, or Grover Norquist's Americans for Tax Reform won't materialize over a gay rights issue.
Now, if Portman strikes a grand bargain on the budget with Obama, that's a whole different story.