For the first time since becoming vice president of the United States, JD Vance has returned to his hometown of Middletown, Ohio, with a goal of rallying Republican voters ahead of November’s pivotal midterm elections.

Vance delivered Friday’s speech at a symbolic location: the steel plant where his late grandfather once worked.

He used the appearance to tout a $1bn investment from the steel manufacturer Cleveland-Cliffs that was supported by $500m in government awards.

That funding, he said, illustrated his party’s commitment to the manufacturing sector and reinvigorating the US economy overall.

“I’m not saying it’s going to be easy – or it’s all going to happen overnight – but in just 18 months, we have seen an explosion of rebuilding in the American heartland,” Vance said, crediting the growth to policies under President Donald Trump.

Vance’s speech comes at a critical time for the Republican Party and Trump in particular.

November’s midterm races will decide whether Republicans are able to maintain control over both chambers of Congress. Should their hold on the legislature slip, Democrats could stymie Trump’s policy priorities for the last two years of his presidency — or even impeach him, as Trump himself has suggested.

Polls have shown that the state of the economy remains the top issue ahead of the midterms.

But how voters perceive each party’s ability to address economic strain has shifted. Before the start of Trump’s second term, the Pew Research Center found that voters were more likely to favour Republican policies on the economy.

In July, however, the dynamic had switched: Thirty-seven percent of those surveyed backed the Democratic approach to the economy, compared with 36 percent for Republicans.

A poll from the news agency Reuters and the firm Ipsos this month likewise found slightly more respondents siding with the Democrats on economic policy than Republicans, upending a longtime trend that stretched back to 2017.

Trump, for his part, has publicly appeared to dismiss cost-of-living issues as a partisan invention, calling questions of affordability a “hoax” and a “con job” engineered by Democrats.

At Friday’s speech, Vance took a different approach, trying to assuage concerns about the administration’s handling of the economy.

“We got a lot of work to do, but we’re making progress on all the things that matter the most,” Vance said, citing efforts to make homeownership more affordable.

The speech is part of an intensifying campaign under Trump to boost the prospects of Republican candidates ahead of the midterms, with the president and other top officials holding rallies for their party’s candidates.

Ohio, part of a historic manufacturing region known as the Rust Belt, has become increasingly conservative since Trump’s first White House victory in 2016.

But amid rising dissatisfaction with Republican leadership, Democrats see a chance to win back the state’s governor’s office, as well as the US Senate seat left vacant when Vance became vice president.

Whoever wins the special election in November will serve the remainder of Vance’s erstwhile Senate term, which would have ended in January 2029.

The Republican nominee in the race, Senator Jon Husted, joined Vance on stage at the Middletown rally on Friday. Husted was appointed to fill Vance’s Senate seat until a special election could be held.

Vance, for his part, dedicated part of his speech to attacking Husted’s Democratic rival, former Senator Sherrod Brown, who lost his re-election race to Republican Bernie Moreno two years ago.

He accused Brown of being among the politicians “who pretend to be friends of the workers in this facility”, while instead advancing their own priorities.

“It’s hard to understand what these modern Democrats actually stand for,” Vance said, characterising the party as having strayed from its ideals.

He pointed to Brown’s record of siding with the policies of former Democratic President Joe Biden, who defeated Trump in the 2020 presidential race.

“[Brown] was a man who claimed to represent this state but never once raised his voice against Joe Biden’s border crisis or against the inflation that was brought on by Joe Biden underinvesting and trying to destroy American industry,” Vance said.

The vice president also singled out Michigan’s Abdul El-Sayed, repeating a false claim that the Democratic Senate candidate called for “Sharia law” in the US.

“I’d love to go back in time and tell my papaw that there’s a man who claims to stand for working people, who says not only should we have Sharia law, but if you criticise it, you are a white supremacist,” Vance said about El-Sayed.

Trump’s approval rating currently sits at 35 percent, according to the Reuters-Ipsos poll from this month.