If Donald Trump wins the GOP presidential nomination, three out of 10 Republican voters say they would not cast a ballot for him in the general election, a new Economist Group/YouGov Poll finds.

Only 71 percent of Republicans and independents who lean that way would vote for Trump if he were to face Hillary Clinton in a general election; 8 percent would vote for Clinton, 10 percent for another candidate and 10 percent would not vote.

In the less likely scenario Bernard Sanders is the Democratic nominee, 70 percent would vote for Trump, 13 percent would vote for Sanders, 10 percent for another candidate and 8 percent would not vote.

Despite the reluctance among some Republicans to support Trump, he was the most popular GOP candidate among the poll’s more than 1,100 respondents: 37 percent said they want Trump to be the Republican nominee compared to 22 percent who want Texas Sen. Ted Cruz, 18 percent who want Florida Sen. Marco Rubio and 9 percent who want Ohio Gov. John Kasich.

Many of the respondents who support someone other than Trump are not under any illusions that their preference will win: 72 percent predicted Trump will secure the nomination, compared to 11 percent who predicted Cruz and 4 percent who predicted Rubio.