Republican voters’ views on marriage equality have changed to the point that opposing the freedom to marry may cost candidates votes instead of winning them, a new poll indicates.

In a new NBC News/Marist College poll, about half of likely Republican voters in the Iowa caucus and New Hampshire and South Carolina primaries said opposition to marriage equality is “either ‘mostly’ or ‘totally’ unacceptable in a candidate,” The Washington Post reports.

“Fifty-two percent of likely Republican primary voters in New Hampshire and South Carolina said opposing gay marriage is either mostly or totally unacceptable, while 47 percent of likely Iowa caucus voters agree,” Post blogger Aaron Blake writes.

The three states play an important role in picking presidential candidates. The Iowa caucus and the New Hampshire primary are the first votes of the presidential primary season, and the South Carolina primary is first in the South. Also, the candidate who wins the Republican primary in South Carolina has usually gone on to win the party’s nomination.

The Post offers some caveats about the poll numbers. The wording of the question may have confused some respondents, the paper notes, and significantly, the poll did not ask how voters would respond to a candidate who actively supports equal marriage rights. There will probably be no Republican candidate coming out for marriage equality in the 2016 race, Blake predicts.

Still, the numbers mark an important shift in voters’ thinking. “It’s fascinating that this many likely Republican primary and caucus voters in the earliest states (especially socially conservative ones like Iowa and South Carolina) say they find opposition to gay marriage being unacceptable,” Blake writes. “And it’s a sign of just how quickly this country — and even the GOP — is moving toward embracing it.”