Support for marriage equality is at an all-time high, even among some groups that have historically been resistant — but a majority of Republicans remain opposed, according to a new Gallup poll.

Sixty-four percent of respondents to Gallup’s annual Values and Beliefs poll say same-sex marriage should be legal, the polling organization reports. This percentage is “not meaningfully different” from last year’s 61 percent, but it “is the highest percentage to date and continues the generally steady rise since Gallup’s trend began in 1996,” the group notes on its website. Only 27 percent supported marriage equality that year.

Democrats and independents, who had long backed marriage equality, continue to do so, with percentages of 74 percent and 71 percent respectively in the latest poll. Republican support has nearly tripled since 1996 but remains short of a majority, at 47 percent, two years after the U.S. Supreme Court legalized same-sex marriage throughout the nation. Still, this is the highest percentage ever among Republicans, Gallup reports, and majority support is possible in the near future.

Support by U.S. Protestants, including all non-Catholic Christians, reached the majority level for the first time this year, at 55 percent. “Meanwhile, a majority of U.S. Catholics have consistently supported same-sex marriage since 2011, which is at odds with the Roman Catholic Church’s official position opposing same-sex marriage,” Gallup notes. Catholic support stand at 65 percent in the latest poll.

Support for legal same-sex relations has also continued to grow, coming in at 72 percent in this year’s poll. “Americans have consistently been more likely to say that same-sex relations should be legal than to say that gay marriage should be legally valid, suggesting that the marriage question pushes a moral, religious or cultural boundary for some people that gay relationships do not,” Gallup reports.

The poll was based on interviews conducted May 3-7 with 1,011 people, aged 18 and older, living in all 50 U.S. states and the District of Columbia. The margin of error is plus or minus four percentage points.