Donald Trump made his return to the national political stage on Saturday night at a county fairground in the small town of Wellington in Ohio, where residents had lined the streets and decorated their homes in red, white and blue to celebrate the former US president’s arrival.

“Lorain county is absolutely in Donald Trump’s wheelhouse. That is a place where they love him,” said Doug Deeken, chair of the Republican party in nearby Wayne county. “Whether they are historical Dems or historical Republicans or historical people that did not give a crap and never voted hardly before, they like him.”

Political operatives said Trump’s decision to hold his first post-White House rally in Lorain county — a region west of Cleveland that includes both old steel mill towns and vast expanses of rural farmland — was an obvious choice given local white working class voters’ affinity for the former president. Despite losing the national election, Trump won the Midwestern state of Ohio in November by eight points over Joe Biden; he was the first Republican to win Lorain county since Ronald Reagan in 1984.

Thousands of the former president’s fans swarmed the fairground, decked out in pro-Trump merchandise and keen to tell reporters the 2020 election had been stolen from their favourite politician, who they implored to run again for the White House in 2024.

The one-time reality-TV star, who has not ruled out another White House bid and enjoys overwhelming popularity in most national polls of Republican voters, revelled in the crowd’s cheers of “Trump won!” and “four more years”.

But he also had another reason to fly into north-east Ohio: revenge.

Trump shared the stage in Wellington with Max Miller, a former White House aide who has launched a Republican primary challenge against Anthony Gonzalez, the incumbent local congressman who was one of 10 House Republicans who voted to impeach him for inciting the deadly January 6 insurrection on the US Capitol. Trump was later acquitted in a Senate trial after just seven Republicans in the upper chamber voted to convict him.

“Max’s opponent is a guy named Anthony Gonzalez,” Trump said to boos from the crowd, calling the congressman a “grandstanding Rino” — Republican in name only.

“That’s not the reason I’m doing this, but I just thought I would say, it’s a character trait that is not so good . . . He’s a sellout, he is a fake Republican, and a disgrace to your state,” he added. “He is not the candidate that you want representing the Republican party.”

Trump’s comments underscored the sharp divisions in a Republican party wrestling with how to move forward under a Biden administration — and signalled the role the former president intends to play in next year’s midterms, when Republicans will look to take back control of both chambers of Congress.

He has already endorsed several conservative candidates who are loyal to him — moves allies say will energise the Republican base and critics warn could alienate moderate voters who want to leave the tumult of the Trump era in the rear-view mirror.

The support of more centrist voters is seen as critical in statewide races across the country, including in Ohio, where Republican governor Mike DeWine will seek re-election next year and a large field of Republicans is currently vying for the party’s nomination to replace retiring senator Rob Portman. Neither DeWine nor Portman appeared at Trump’s side on Saturday, citing personal obligations.

“There are Republicans who would prefer that [Trump] would be a kingmaker and not the king himself for the future,” said Bryan Williams, a former chair of the Ohio Republican party. But he added: “It is not a very big number of the people that think that Trump should step off the stage.”

Alex Roth, a Republican consultant working on campaigns in north-east Ohio, said most GOP candidates were now at pains to demonstrate their affinity for Trump.

“Republicans running in primaries right now are running to show their loyalty to the president, and it is shaping the way we are running our campaigns,” he said.

The desire to curry favour with Trump was palpable on Saturday night, with all of the Republican contenders for Portman’s Senate seat in attendance.

Trump has yet to endorse a candidate in that race, but the campaign of Jane Timken, a former state party chair, handed out flyers calling her the “only true pro-Trump, America First” candidate. At one point during his freewheeling, 90-minute speech, the former president asked the crowds to cheer for the candidate they wanted him to support.

He is not without his critics in the Ohio Republican establishment. John Kasich, the state’s former GOP governor and one-time presidential candidate, endorsed Biden ahead of last year’s election.

But few Republicans in Ohio are willing to go on the record criticising the former president, illustrating the long shadow he continues to cast on the party and its future.

Brad Kastan, a longtime Republican donor based in Columbus, is a rare exception.

“For conservatives and Republicans to succeed, we can’t be dependent on any one person, or personality, and I worry if we get too bogged down in what is sometimes divisive . . . we are going to end up with a Georgia on our hands,” he said, referring to the one-time Republican southern state that now has two Democratic senators.

A Republican operative, who asked not to be named, said: “The party needs to consider the fact that voters do not just vote because of President Trump. They vote because of the stuff that he did. I think that message is kind of getting lost.”

Another GOP insider, who also asked for anonymity, said they were no fan of Trump. But they conceded the former president would inevitably play a big role in Republican politics.

“Are you going to ask a doctor what they think of the femur?” they asked. “Trump exists. He is part of the political reality for both Republicans and Democrats. The phenomenon that he creates is just something that we have got to deal with. You can’t go around removing people’s femurs.”