He wrote that on learning that one of his sons is gay he "wrestled with how to reconcile my Christian faith with my desire for Will to have the same opportunities to pursue happiness and fulfillment as his brother and sister."
He is not the only prominent Republican to come to this view in this way. Former Vice President Dick Cheney is another.
And at the Conservative Political Action Committee convention, a panel sponsored by the Competitive Enterprise Institute drew a large and approving crowd for a discussion labeled, "A Rainbow on the Right: Growing the Coalition, Bringing Tolerance Out of the Closet."
It's clear now that support for same-sex marriage crosses party lines. That's what one might expect, from polls that show a huge shift of opinion on this issue over the last two decades.
In the early 1990s, large majorities opposed same-sex marriage. In 1996, Bill Clinton didn't hesitate before signing the Defense of Marriage Act, which barred the federal government from recognizing same-sex marriages. He now urges its repeal.
In 2004, after the Massachusetts Supreme Judicial Court by a 4-3 margin discovered that the state's 1780 Constitution required recognition of same-sex marriages, George W. Bush supported the Family Marriage Amendment, which would bar such marriages across the nation.
That was never going to be ratified, but it did help Bush mobilize tradition-minded voters in states like Ohio in the 2004 election.
Now many polls show majorities or pluralities of Americans favor same-sex marriage. Last November, voters in Maine, Maryland and Washington approved same-sex marriage.
Voters in Minnesota rejected a constitutional amendment that would ban it. That's in contrast to the results in 30 states, all but one of them in 2008 or earlier, where voters approved similar amendments.
Many of those states would surely vote the other way now, including California, whose 52-to-48 percent vote against same-sex marriage in 2008 was overturned by federal trial and appeals courts in a case now before the Supreme Court.
The Supreme Court could rule that the Constitution requires same-sex marriage everywhere. Or it could affirm the appeals court's rationale, which applies to California only.
Or it could say that the Constitution leaves this issue to the states. That's the outcome that, as a supporter of same-sex marriage, I prefer.
Nine states and the District of Columbia have legalized same-sex marriage, most by legislative or popular vote. Another 11 states have no constitutional amendment barring it.
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