Seventy-nine percent of Democrats said they would approve of Vice President Kamala Harris becoming the Democratic presidential nominee if President Joe Biden steps aside, according to a new Economist/YouGov poll.

Twenty-eight percent of Democrats think Harris would be more likely than Biden to win against former President Donald Trump in the fall, while 32% say Biden and Harris have about the same chances of winning. Less than a quarter say Biden would be more likely than Harris to defeat the former president.

The results come as Biden faces renewed calls to drop out of the race from Democrats who worry the president doesn’t have what it takes to win back the White House in November. Former Speaker of the House Nancy Pelosi (D-CA) is reportedly working behind the scenes, speaking with Democrats who have called on Biden to step down, and Biden is opening up to those calls.

Forty-four percent of Democrats think Biden should definitely or probably step aside as the nominee, compared to 41% who believe he should not, according to the poll.

Among Democrats who think Biden should drop out of the race, 68% list concerns over his age, health, or cognitive function as the biggest reasons why, while 23% say the main reason is concerns over the president’s ability to defeat Trump.

However, only 16% of Democrats and 19% of voters think it’s “very likely” or “somewhat likely” Biden will step aside.

Rep. Adam Schiff (D-CA) called for Biden to pass the torch Wednesday, the first elected Democrat to do so publicly since Trump was shot at a Pennsylvania rally Saturday. 

Biden has said he is committed to staying in the race but admitted in an interview aired Wednesday that he would consider dropping out if a medical condition emerged.

The poll was conducted between July 13-16 among 1,582 adult U.S. citizens.