Former president Donald Trump has extended his lead after President Joe Biden’s rocky debate performance last week, according to the latest presidential poll.

Nonpartisan Patriot Polling showed 44% of registered voters were planning to cast a ballot for Trump, the presumptive Republican nominee, over 41% who were backing Biden, a Democrat. Slightly more than 11% supported independent Robert Kennedy and 4% were unsure. The results show that Trump has doubled his lead since the organization’s last poll in February.

Among those polled, 76% said Trump won Thursday’s debate in which Biden sometimes seemed confused and appeared to struggle with his words. Biden’s approval rating has also dropped since the group’s last poll, falling from 33% in February to 29% in June, something pollsters described as a “precarious position for an incumbent seeking reelection.”

The nationwide poll was conducted among 1,029 registered voters between June 27-29. The margin of error was plus or minus 3 percentage points.

Trump is also ahead of Biden – albeit by a closer margin – in FiveThirtyEight’s average of recent national polls. That shows Trump leading Biden 42% to 40%. Kennedy is polling at 9%.

The same polling average saw Biden leading by a slim margin as recently as a week ago.

Trump against other Democrats

With calls growing for Biden to step aside, another set of polling numbers suggests that might not help the Democrat’s cause.

Data For Progress polling shows none of the possible Democratic contenders – including Vice President Kamala Harris – outpolling Trump. In a head-to-head matchup, 48% of likely voters said they preferred Trump over Harris, the choice for 45%. Trump holds similar advantages over a host of possible Democratic contenders including Secretary of Transportation Pete Buttigieg, U.S. Sen. Cory Booker of New Jersey and California Gov. Gavin Newsom, all of whom have been mentioned as possible Biden replacements.

The Data For Progress poll showed only 51% of Democrats and 35% of likely voters thought Biden should remain as the Democratic nominee, a 12-point drop among Democrats since the same question was asked in March.

The Data for Progress poll was conducted among 1,011 likely voters with a margin of error of plus or minus 3 percentage points.