The decision by the Senator Rob Portman, a Republican from Ohio, to announce his support for same-sex marriage may come to be seen as a watershed moment for gay rights advocates. Mr. Portman’s announcement, which he said he made in part because his son is gay, has so far yielded relatively little pushback from Republicans on blogs and social media, or from other Republican office-holders. Instead, gay rights advocates are increasingly finding support from influential Republicans.
But the rank and file of the Republican Party may be different, and the polling suggests that they have largely not changed their views on same-sex marriage.
According to Pew Research polls conducted each year, support for same-sex marriage has increased to 62 percent from 43 percent among Democrats since 2001. Among independent voters, support has risen to 52 percent from 43 percent over the same period. However, only 25 percent of Republican voters supported same-sex marriage in Pew’s poll last year, barely changed from 21 percent in 2001.
Polling subsamples of voting groups like Republicans can entail high margins of error, but the Pew poll is largely consistent with other recent surveys.
According to an average of seven recent surveys on same-sex marriage, as shown in the chart above, only 26 percent of Republicans support same-sex marriage rights as compared with 54 percent of independents and 66 percent of Democrats. Attitudes among Republican voters may shift on the issue by 2016, particularly if more respected conservatives like Mr. Portman announce their support for same-sex marriage, but it is less than clear that his position will reflect a broadly acceptable viewpoint among Republican primary and caucus voters by that time.