Republicans remain divided on the question of whether delegates should vote their conscience at the party’s convention next month—a move that could block Donald Trump from the nomination for president. An effort by some delegates to the Republican National Convention in Cleveland to insert a “conscience clause” that could free delegates from voting for Trump on the first ballot is gaining some support from elected officials.

In recent weeks, some prominent Republicans have voiced support for permitting delegates to vote as they wish on the first ballot, including House speaker Paul Ryan, who advised delegates last Sunday to follow their “conscience.”