Will Trump Run as a Felon? A Big 2024 Question Will Soon Be Answered.

The witness list is winding down. Closing statements could come as early as Tuesday. Then a Manhattan jury will gather in the first criminal trial of a former president to determine whether Donald J. Trump will campaign this fall as a convicted felon.

The political impact of one of the most consequential jury deliberations in the nation’s history is far from predictable.

“Who knows?” said Mike Murphy, a Republican strategist who has been a longtime Trump critic. “The first casualty of the I’m-right-you’re-evil politics of today is institutional credibility. We’re not in the politics of accepting impartial facts anymore.”

But whether the verdict becomes a political turning point or not, it will be a pivotal moment in the race.

The case is the only one of Mr. Trump’s four indictments expected to come to trial and a conclusion before Election Day, even if the charges of falsifying financial records related to a hush-money payment made to a porn star do not match the gravity of the indictments accusing Mr. Trump of trying to thwart the peaceful transfer of power in 2020.

There is little doubt that Mr. Trump’s base is unlikely to abandon him now. Less clear is how swing voters or some of the traditional Democratic constituencies — younger, Black and Hispanic voters — who have expressed diminished support for Mr. Biden lately, and even flirted with Mr. Trump, would process a guilty verdict.