Controversies Erupt as Trump and G.O.P. Make Critical Push to Voters

A Republican who reportedly called himself a “Black Nazi,” a false story about migrants eating cats and dogs, and a feud with Taylor Swift bring back a sense of chaos.

Even by the standards of a head-spinning presidential campaign, Donald J. Trump’s campaign over the past two weeks has been tumultuous.

A period that began when Mr. Trump pushed baseless claims from the debate stage that immigrants in Ohio were stealing and eating household pets ended with him facing attacks over his support of the Republican candidate for governor in North Carolina, who referred to himself as a “black Nazi” on the message board of a pornographic website.

In between, Mr. Trump invited Laura Loomer, a right-wing influencer known for promoting Sept. 11 conspiracy theories, to join him at events commemorating the anniversary of the attacks. He urged a government shutdown, attacked a cornerstone of his own tax policy, declared “I HATE TAYLOR SWIFT!” on social media after she endorsed his rival and — at events intended to woo Jewish voters — said “the Jewish people” would be responsible if he lost the election, prompting fears of antisemitic reprisal.

While Vice President Kamala Harris crisscrosses the battleground states pressing her message about Mr. Trump being a danger to abortion rights, democracy and the country’s future, Republicans have been re-immersed in the kind of drama that has defined the former president’s political brand for more than a decade.

In the past, such a drumbeat of controversy in the final weeks of the campaign might have given voters pause, even prompting shifts in the race. But this year, the nation has met the crush of chaos with little more than a shrug and, some strategists say, a desire to tune out the campaign altogether.

“We are on overload with wild stories every news cycle,” said David Kochel, a longtime Republican strategist and a veteran of several presidential campaigns. “It’s absolutely overwhelming the capacity of people to track politics. You can’t keep up with it all, so a lot of people just tune it out.”