President Joe Biden is holding a 1-point lead over former President Donald Trump in a national survey released Thursday as the two head toward a likely rematch in November.

The Reuters/Ipsos poll found Biden leading Trump with 39 percent of support among registered voters, compared to the former president’s 38 percent. The one-week poll, which closed Wednesday, also shows that 12 percent of its respondents said they don’t know who they would vote for or would not vote at all, while 11 percent would back some other candidate.

Biden and Trump each clinched enough delegates to become the presumptive nominees for their respective parties Tuesday. According to The Hill/Decision Desk HQ’s polling average, Trump is leading Biden by about 1.4 percentage points nationally.

Reuters noted that its poll found Trump leading Biden in seven states where the races were the closest in 2020, with 40 percent of registered voters backing the former president and 37 percent backing Biden. The poll also found that when Robert F. Kennedy Jr. appeared as a third candidate, 15 percent of registered voters in those states backed him, according to the news service.

The poll also found that only 37 percent of Nikki Haley’s supporters said they would vote for Trump after she dropped out of the GOP presidential primary last week, Reuters noted. About 16 percent said they would vote for Biden, while the rest said they would vote for someone else or not vote at all.

The poll collected responses from 4,094 U.S. adults, including 3,356 registered voters, from March 7-13. The margin of error among registered voters was 1.8 percentage points and 1.7 percentage points for all respondents.