Public support for the legality of same-sex marriage first reached a majority in 2011, when 53% supported it. Since then, support has ranged from 48% to 55%. The five-percentage-point increase in this year's Values and Beliefs poll, conducted May 6-10, is the largest year-to-year climb since 2011, when support rose by nine points.
Support for the legality of gay marriages in the U.S. has been a fast-changing trend. Just two decades ago, only 27% of Americans backed gay marriage, while 68% opposed. By 2005, the percentage in favor had increased by 10 points to 37%, and by 2010 it had reached 44%.
The record high in support comes roughly one month before the Supreme Court is to issue a ruling on the constitutionality of same-sex marriage. Americans, at this point, are not highly familiar with the case, with 42% following it closely -- well below the average 60% for news issues Gallup has measured over the past two decades. Attention to the case is similar among supporters and opponents of gay marriage.