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A new poll shows 50% of voters have already decided not to support Trump

According to a new poll by Monmouth University, President Trump is slated to be the first one-term president since 1993. The poll, released Thursday, adds to recent worrying results for Trump. It also reflects a specific challenge that Trump is facing, which is that a significant amount of voters have apparently already decided they won't vote for him — more than have decided they're definitely voting for his likely Democratic opponent, Joe Biden.

With four months until November's general election, the results from this poll are telling. The poll found that 53% of registered voters support Biden and 41% plan to back the president. According to respondents, Biden is likely to edge out Trump even though he himself is decreasing in popularity: Monmouth wrote in its results that "overall, 21% of all registered voters do not have a favorable opinion of either party’s nominee."

This scenario in which voters aren't keen about either candidate isn't so different from the 2016 presidential election. Then, 53% of voters felt unfavorably about Trump, according to Monmouth. Of course, Trump overcame those numbers to win four years ago, and with his unfavorable rating hovering around a similar 55% per Monmouth's latest poll, perhaps he could defy the odds again.

Still, a lot has changed politically and socially since his last run for office. First, many voters have an unfavorable opinion specifically about how Trump has dealt with the coronavirus pandemic, which as of July 2 has killed upward of 128,000 Americans. But there's another reason why 50% of registered voters say they won't support Trump and only 39% said the same thing about Biden: "Concerns about the two septuagenarians’ faculties have become prominent in recent media coverage and internet memes."

Just 52% of voters surveyed were at least "somewhat confident" in Biden's mental faculties and physical stamina. Only 45% of voters felt the same about Trump. But more Trump voters than Biden voters say that they're confident in the health of their candidate of choice, which Monmouth University Polling Institute Director Patrick Murray said is due to Trump supporters' tendency to "offer [their] support without qualification."

Biden has enough delegates to clinch the Democratic nomination, but he won't be the official candidate until the nominating convention in August. His campaign overcame a lackluster start en route to victory — he came in fourth in the Iowa caucuses — but has experienced some lack of enthusiasm among voters. Earlier this year, too, the candidate was hit with a sexual assault allegation that hasn't gone away, while the most progressive voters worry he's too middle-of-the-road for the moment.

Conducted between June 26-30, the poll interviewed 733 registered voters by phone. It has a margin of error of 3.6 percentage points.