Former Vice President Joe Biden Joe BidenSenate Republicans face tough decision on replacing Ginsburg What Senate Republicans have said about election-year Supreme Court vacancies Biden says Ginsburg successor should be picked by candidate who wins on Nov. 3 MORE is 9 points ahead of President Trump Donald John TrumpObama calls on Senate not to fill Ginsburg's vacancy until after election Planned Parenthood: 'The fate of our rights' depends on Ginsburg replacement Progressive group to spend M in ad campaign on Supreme Court vacancy MORE in Arizona, according to an OH Predictive Insights poll released Tuesday morning.

The poll showed Biden leading Trump 52 percent to 43 percent with 5 percent of voters undecided, up from the 6-point lead the former vice president had in March.

Though the poll shows positive signs for Biden in the important swing state, the pollsters noted that 78 percent of the former vice president's supporters said they were "extremely enthusiastic" or "very enthusiastic" about the election compared with 88 percent of Trump's supporters.

“If Coronavirus is still rampaging through the country in November, campaigns may struggle to turn out voters on Election Day,” says Jacob Joss, data analyst at OHPI. “That task is going to be made even more difficult if a candidate’s supporters are not enthusiastic about voting for them in the first place. While the president faces a significant deficit, in these unprecedented times he is by no means out of this race."

The poll was conducted April 7-8 among 600 likely Arizona voters with a reported margin of error of 4 percentage points.