• It's not clear what impact the criminal conviction of Donald Trump will have on his presidential campaign against President Joe Biden.
• Recent polls show only a small fraction of non-Democratic voters would be less likely to vote for Trump over a guilty verdict in his hush money trial.
• But in a consistently tight race with two well-known candidates targeting a small-but-important slice of swing voters, any shift in opinion resulting from the guilty verdict could have an outsize effect.

Donald Trump is now the first former American president ever to be convicted in a criminal trial — but it's far from clear whether that black mark will sink, or even weigh down, his bid to unseat President Joe Biden.

Recent polls suggest that the guilty verdict could affect how key voting blocs view Trump, the presumptive Republican presidential nominee.

But any change may not be enough to change the trajectory of the presidential race, according to the latest poll finding that only a small fraction of non-Democratic voters would be less likely to vote for Trump if he is found guilty in the hush money trial.

Nearly three-fourths of registered independents said that a guilty verdict against Trump would make no difference to their vote, according to the survey from NPR/PBS NewsHour/Marist released Thursday morning.

Just 11% of those respondents said that outcome would make them less likely to back Trump in November, while 15% of the group said a guilty verdict would more them more likely to support him.

Among Republicans, 25% said they will be more inclined to vote for Trump if he is found guilty in New York, versus 10% who say they will be less likely to do so.

Those answers echo the results of a recent Quinnipiac University poll, in which just 6% of Trump voters said they would be less likely to vote for him if convicted, while nearly a quarter said they would be more likely to vote for him.

However, 23% of independent registered voters in that poll said a Trump conviction would make them less likely to back him.

"It's a strange situation where a criminal conviction probably makes little difference" politically, said Erik Gordon, a professor at the University of Michigan's Ross School of Business, in an interview.

Most people on either side of the political spectrum have already made up their minds about Trump, the professor explained.

"The only thing that could hurt trump at this point would be if somebody has a TikTok of him kicking a cat," he quipped.

Compared with a Politico Magazine/Ipsos poll in March — which found 36% of independents would be less likely to vote for a convicted Trump — the more recent survey results suggest a decline in the potential impact of the hush money verdict.

On the one hand, the poll findings indicate that the outcome of Trump's trial ultimately will not sway the vast majority of voters.

But in a consistently tight race with two well-known candidates targeting a small-but-important slice of swing voters, any shift in opinion resulting from the guilty verdict could have an outsize effect.

Still, few events in the unusual presidential rematch have so far made a clear, measurable impact on the state of the contest.

Despite being weighed down by numerous lawsuits, dozens of criminal charges, and a regular stream of scandals and gaffes, national polling trackers show Trump is in an extremely close national race with Biden and leading slightly in key battleground states.

Biden's White House and reelection campaign, meanwhile, have been dogged by consumer woes about inflation — consistently one of voters' top concerns — despite their efforts to spread a more positive message about the growing U.S. economy.

NPR/PBS NewsHour/Marist polled 1,261 U.S. adults from May 21 to May 23 with a margin of error of 3.4 percentage points. For the 907 registered voters polled who definitely plan to vote in the Nov. 5 election, the margin of error rises to 4.1 percentage points.

Quinnipiac polled 1,374 registered U.S. voters from May 16 to May 20, with a margin of error of 2.6 percentage points.

This Politico Magazine/Ipsos poll of 1,024 U.S. adults was conducted March 8 to March 10. It has a margin of error of 3.3 percentage points.