WASHINGTON — Three and a half years ago, President Donald Trump incited a violent riot at the Capitol in a bid to overturn Joe Biden’s election victory and remain in power, a special House committee concluded after a lengthy investigation.

On Thursday, Trump will make his first visit to Capitol Hill since before the Jan. 6 attack as Republicans give a hero’s welcome to their party’s presumptive 2024 nominee.

Less than five months before his rematch with Biden, Trump is scheduled to meet behind closed doors just blocks from the Capitol with House Republicans in the morning and GOP senators in the afternoon as the party discusses campaign messaging and its legislative strategy in 2025.

Trump and Biden are locked in a competitive race, and control of Congress is up for grabs this fall, but many in the GOP express optimism about sweeping the 2024 elections and acting swiftly on Trump’s agenda.

“It will be an expression of unity,” Sen. Roger Wicker, R-Miss., a past GOP campaign chairman, told NBC News.

Even some critics in the party plan to attend: Sen. Bill Cassidy, R-La., who voted to convict Trump in the impeachment trial after the Jan. 6 attack, said he thinks he will attend but is still firming up his schedule.

“The polls say he’s going to be our next president, so you got to work with the guy,” Cassidy said, joking that he does not know what to expect. “Can you predict what Trump’s going to do the next minute? No, of course not.”

It will also be the first time since the Capitol riot that Trump will have been in the same room with Senate Minority Leader Mitch McConnell, R-Ky.; the two have not spoken since December 2020. At the time, McConnell slammed Trump as being “practically and morally responsible for provoking the events” of Jan. 6. He has since endorsed Trump for president — and announced that he will step down as Senate GOP leader after this year.

“I said three years ago right after the Capitol was attacked that I would support our nominee, regardless of who it was — including him. I’ve said earlier this year I support him. He’s earned the nomination by the voters all across the country,” McConnell told reporters Tuesday, without using Trump’s name. “And of course, I’ll be at the meeting tomorrow.”

Trump returns to Washington just after he was convicted of 34 felony counts of falsifying business records related to hush money payments to an adult film star and as he awaits sentencing. Between meetings with House and Senate Republicans, Trump will sit down with CEOs in a meeting with the Business Roundtable, a lobbying group that says it represents more than 200 major companies, as Washington and key industries prepare for the reality that Trump might be president again.

Several top contenders to be Trump’s running mate will have a chance to catch his attention Thursday, as well. They include GOP Sens. JD Vance of Ohio, Marco Rubio of Florida and Tim Scott of South Carolina.

House Speaker Mike Johnson, R-La., a top Trump ally who played a key role in the GOP’s effort to stop certification of Biden’s 2020 victory, predicted that Trump would win a second term and would be “the most consequential president of the modern era” as he fixes the “disaster” created by the Biden administration.

“When he comes in, we’ve got to have a very aggressive first-100-day agenda; the first year will be important. I think we cannot waste a moment, because there are so many things to do,” Johnson told reporters Wednesday. “You don’t put the cart before the horse, but you do have to be prepared to lead.”

Other Trump critics in the party are expected to skip the Senate meeting, including Sens. Lisa Murkowski of Alaska, Susan Collins of Maine and Mitt Romney of Utah. All three voted to convict Trump after he was impeached in connection with Jan. 6.

Romney, who is retiring from the Senate this year, said he has a flight to catch at the time of the Trump gathering.

“I don’t give him advice on what to say, and I’m sure he wouldn’t listen to my advice anyway,” Romney told reporters.

Sen. Thom Tillis, R-N.C., said he does not read much into McConnell’s attending the meeting with Trump.

“I don’t think it’s anything more than Mitch showing respect for our presidential nominee,” Tillis said. “And showing up for the rest of us in the conference.”

Trump is not expected to set foot in the Capitol complex itself, which his supporters overran in 2021, during his visit. He will huddle in the morning with House Republicans at the Capitol Hill Club, a private Republican club just steps from the Capitol office buildings. In the afternoon, he will meet with GOP senators at the National Republican Senatorial Committee headquarters after he addresses the Business Roundtable.

Sen. Todd Young, R-Ind., who has not endorsed Trump for president, declined to say whether he will attend.

“No Trump questions,” Young said, adding that it is a personal rule “until I decide to make it no longer a rule.”