(Kristin Lenz / The Washington Post)

After years of defeats, same-sex-marriage advocates scored a remarkable 4-0 sweep of state ballot contests on Nov. 6. One major reason: This year, significant numbers of Republicans voted their way. That should give pause to a GOP establishment that has alienated many younger voters and independents with its stance on the issue and now faces the prospect of dissent among its core constituents as well.

The evidence comes straight from a close study of the election returns in Maryland, Maine and Minnesota. (Washington state, with its unique system of mail voting, has been slower to report its results in detail. I’ve based my analysis on the other three states that had same-sex-marriage contests.)

Let’s break it down.

The Maryland ballot referendum, Question 6, essentially asked voters to confirm or reject a new law allowing same-sex marriage. In 11 of the 18 counties that Mitt Romney carried, Question 6 fared better than President Obama, a sign that GOP voters had crossed over in support. While the phenomenon could be seen everywhere from farm towns to blue-collar inner suburbs, the biggest swings tended to come in affluent bedroom communities. At one precinct in Hunt Valley, north of Baltimore, with 2,116 votes cast, there was a 28 percentage-point swing, leading to a landslide for Romney and the ballot question: Obama drew a paltry 37 percent, but Question 6 carried the precinct with a whopping 65 percent.

The margins weren’t as large in other precincts, but swings of 10, 15 and 20 points were common. (I should mention that I volunteered on my own time for the Question 6 effort, working especially among libertarians and conservatives on its behalf.)

In Minnesota, where voters were asked to ban same-sex marriage through a state constitutional amendment, precinct returns show that suburban Republicans broke from their party in droves to defeat the ban. According to the Pioneer Press of St. Paul, 47 towns around the Twin Cities area voted for Romney while opposing the measure, known as Amendment One. Exurban Scott County, the state’s fastest growing, narrowly turned down Amendment One, even as it gave Romney a comfortable 56.5 percent of its vote.

To be sure, rural parts of Minnesota saw ticket-splitting the other way, with some Democratic-leaning areas backing the marriage ban. But within commuting distance of the Twin Cities, the defections from the Republican line were deep and unmistakable. Romney won easily in such lakeside Hennepin County towns as Orono, Deephaven and Shorewood. Conventional wisdom would have them voting for the marriage ban as well — but they rejected Amendment One by 60 percent or more, an outcome that suggests a significant change in demographics and attitudes from even a decade ago.

In the large and politically competitive middle-class suburb of Eagan, Minn., home to former GOP governor Tim Pawlenty, Romney wound up losing by nine points, about the same as his statewide margin. That was close, though, compared with the results for Amendment One, which Eagan voters buried by a 22-point margin.

One quick way to look for towns where Republicans were especially likely to approve same-sex marriage is to consult the state-by-state Yahoo.com “Best Places to Live” series, which highlights communities with high incomes, high education levels and low rates of property crime. The list of “Best Places to Live in Minnesota” is dominated by outlying Twin Cities suburbs, most of which tilt strongly GOP: Sixteen of the 20 supported Romney — six of them by 60 percent or more. But only one town among the 20 voted to ban same-sex marriage, and by an anemic 50.28 percent (had nine voters there switched sides, the outcome would have been different).

Maine voters were asked to legalize same-sex marriage through a referendum that lost narrowly in 2009. This time it won, with 53 percent of the vote. Again, Republicans helped secure the victory.

Maine, unlike Maryland and Minnesota, has a shortage of classic Republican bedroom suburbs; most of the suburbs of its only sizable city, Portland, lean Democratic. Consider, however, the five towns atop Yahoo’s “Best Places to Live in Maine” list. The Bangor suburb of Hampden voted both for Romney and for freedom to marry. The other four towns, all Portland suburbs — Cumberland, Falmouth, Yarmouth and Cape Elizabeth — went for Obama by votes ranging from 53 to 63 percent, and then in each case registered a further 10- to 13-point swing toward same-sex marriage.

Fox News sponsored exit polls in each of the three states; of self-described Republicans, between 21 percent and 25 percent said they were breaking from the party’s official position in their vote. The pollsters asked voters which was closer to their own view: “Government is doing too many things better left to businesses and individuals” or “Government should do more to solve problems.” Of voters who said government is doing too much — prime prospects for anyone trying to assemble a majority Republican coalition — 34 percent to 38 percent sided with same-sex marriage advocates.

So where next for the Republican Party on this issue? Despite the GOP’s historic identification with individual liberty and with getting the government’s nose out of citizens’ business, no one expects it to endorse same-sex marriage anytime soon. But one plausible path would be a GOP call for leaving the issue to the states, with New York going one way, for instance, and Texas another. That would probably capture a consensus among a broad range of active Republicans, fit reasonably well with the party’s other ideological stands and still distinguish its position from the Democratic Party’s support for same-sex marriage in its 2012 platform.

The GOP has left itself little room to maneuver. When some in the Romney campaign took an interest in the “leave it to the states” position this fall, they discovered that the candidate, like several of his former rivals for the nomination, had already signed a pledge circulated by the National Organization for Marriage committing him to support a constitutional amendment to ban same-sex marriage. Although many national polls now show support for marriage equality, the national Republican platform continues to endorse the same deeply out-of-touch proposal.

If and when the party’s leadership changes its mind, a whole lot of suburban Republicans will be murmuring under their breath, “About time.”


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Walter Olson is a senior fellow at the Cato Institute and the author of “Schools for Misrule.”