WASHINGTON — President Trump has launched his general election campaign not merely rewriting the history of the January 6, 2021, attack on the Capitol, but positioning the violent siege and its failed attempt to overturn the 2020 election as a cornerstone of his bid to return to the White House.

At a weekend rally in Ohio, his first as the presumed Republican Party presidential nominee, Mr. Trump stood onstage and raised his hand in salute to the brim of his red Make America Great Again hat, as a recorded chorus of prisoners in jail for their roles in the January 6 attack sang the national anthem.

An announcer asked the crowd to please rise “for the horribly and unfairly treated January 6th hostages.” And people did, and sang along. “They were unbelievable patriots,” Mr. Trump said as the recording ended.

Mr. Trump’s view of the history of January 6, which he amplified during the early days of the GOP primary campaign to rouse his most devoted voters, remains a rally centerpiece even as he must appeal more broadly to a general election audience.

Having previously vowed to pardon the rioters, he promised to help them “the first day we get into office.”

In heaping praise on the rioters, Mr. Trump is shifting blame for his own role in the run-up to the bloody mob siege and asking voters to absolve hundreds of them — and himself — over the deadliest attack on a seat of American power in 200 years.

At the same time, Mr. Trump’s allies are installing 2020 election skeptics to the Republican National Committee, further institutionalizing the claims that spurred the violence. That raises red flags about next year, when Congress will again be called upon to certify the vote.

They’re not alone. Republicans in Congress are embarking on a re-investigation of the January 6 attack that seeks to shield Mr. Trump of wrongdoing while lawmakers are showcasing side theories about why thousands of his supporters descended on Capitol Hill in what became a brutal scene of hand-to-hand combat with police.

Five people died in the riot and its aftermath, including one person killed by Capitol police.

Mr. Trump is facing a four-count federal indictment over January 6 and its leadup, including charges he conspired to defraud Americans over his 2020 election defeat and obstructed the official proceeding in Congress to certify the vote for President Biden. 

As the Supreme Court considers Mr. Trump’s claim that he should be immune from prosecution, it’s unclear when the case will go to trial, raising the possibility it might not be resolved until after the election.

The initial House Select Committee on January 6 found that Mr. Trump criminally engaged in a “multi-part conspiracy” to overturn the lawful results of the 2020 presidential election and failed to act to stop his supporters from attacking the Capitol and beating police.

More than 1,200 people have been charged in the riot, including far-right Oath Keepers and Proud Boys extremists, with hundreds convicted. Mr. Trump’s lawyer, Mayor Giuliani, and attorney John Eastman face legal challenges over their work on the 2020 election.

Mr. Trump’s campaign, in response to an inquiry from the Associated Press, pointed to the work from the House investigators who are trying to show inconsistencies in the Select Committee’s probe and its star witness, a former Trump aide, Cassidy Hutchinson, who had a front-row seat to inner workings at the White House.

Mr. Trump’s national press secretary, Karoline Leavitt, said the Justice Department has spent more time prosecuting the former president and “targeting Americans for peacefully protesting on January 6th” than other criminals.

“President Trump will restore justice for all Americas who have been unfairly treated,” she said.

Even as Republicans worry privately that Mr. Trump risks turning off women and independent voters he would need in the general election rematch against Mr. Biden, top aides have said there is only so much they can do as Mr. Trump is going to be Mr. Trump.

Over the weekend, Mr. Trump focused his attention on the former Republican congresswoman, Liz Cheney, who was vice chairwoman of the Select Committee and personally secured Ms. Hutchinson’s blockbuster 2022 testimony.

“She should go to Jail along with the rest of the Unselect Committee!” Mr. Trump posted on social media.

Ms. Cheney posted in response — “Hi Donald: you know these are lies” — as she has worked to dispel falsehoods about January 6.

“If your response to Trump’s assault on our democracy is to lie & cover up what he did, attack the brave men & women who came forward with the truth, and defend the criminals who violently assaulted the Capitol,” Ms. Cheney said in one post, “you need to rethink whose side you’re on. Hint: It’s not America’s.”

Many Republicans are willfully ignoring the issue, especially in Congress, despite lawmakers having run for their lives and taken shelter as the rioters stormed the Senate chamber and ransacked Capitol offices.

Senators who sharply criticized Trump after the January 6 attack, like the Republican leader, Mitch McConnell, and South Dakota’s John Thune, the No. 2 Senate Republican, have now reluctantly endorsed him.

Others are still declining to endorse Mr. Trump, including Senator Cassidy of Louisiana, who voted to convict Mr. Trump in his second impeachment on the charge of inciting the insurrection for the January 6 attack. The Senate discovered Mr. Trump to be not guilty of that accusation.

The holdouts, though, are in the minority. Appearing on NBC’s “Meet The Press,” Mr. Cassidy would only say, “I plan to vote for a Republican for the presidency of the United States.”

One Republican willing to speak out is Vice President Pence, whom rioters shouted they wanted to “hang” that day as a makeshift gallows stood on the Capitol’s West Front.

“I was there on January 6th. I have no doubt in my mind … that some people were caught up in the moment,” Mr. Pence said on CBS’s “Face the Nation.”

“But the assaults on police officers, ultimately an environment that claimed lives, is something that I think was tragic that day,” Mr. Pence said. “And I’ll never diminish it.”