Down in the polls, eclipsed in fundraising by an energised Democratic Party and desperately trying to move debates to Fox News, Donald Trump has found himself in a hugely different position from where he was just one month ago.

After a disastrous debate performance from Joe Biden and a failed assassination attempt on his life, Trump was leading in the polls and betting markets before Kamala Harris replaced Joe Biden as the Democratic nominee.

Trump is now facing a much younger opponent than Biden, highlighting his age in the process, and is facing a credibility problem with voters as his campaign rages against polls showing him behind Harris.

The swing states

New polling from CBS/YouGov has Trump and Harris neck and neck in the key swing states of Pennsylvania, Wisconsin, Arizona, Georgia, Nevada and North Carolina.

Momentum and several key moments, including her VP pick and the Democratic National Convention, are still to come for Harris.

Brian Hughes, a senior adviser to Trump’s campaign, claimed the poll had inflated results for her.

“The Fake News Media continue to help dangerously liberal Kamala hide her record of economic failure and soft-on-crime policies,” he said.

“The American people are seeing through it and will not allow this national gaslighting campaign to win.”

Trump was five points up in the same general election poll before Biden left the race, but Harris is now leading him by a point.

Harris interviewed three potential VPs over the weekend, with two of them, Arizona senator Mark Kelly and Pennsylvania governor Josh Shapiro, hailing from two states that could be key to victory.

Arizona senator Mark Kelly (right), and his twin brother Scott, were astronauts before his political career. Photo: NASA

David R Berman, professor emeritus of political science at Arizona State University, said although Republicans currently outnumber Democrats by party numbers in Arizona, Democrats have increasingly performed well in the state.

“Putting Harris on the ballot in place of Biden has rejuvenated the Democrats,” he said.

“Overall, there is the possibility of considerable change in voter sentiment as the election campaigns unfold. Arizona is a state that can go either way.”

The Vance problem

The selection of JD Vance as Trump’s running mate is proving another headache for the Republican candidate, who selected the 39-year-old to shore up his base against Biden.

Vance has proven hugely unpopular with American voters and his past criticisms of Trump and his comments about “childless cat ladies” have come back to haunt him.

He hit back against Jennifer Aniston and Democrats who latched onto the comments from 2021 by saying that they were “disgusting because my daughter is two years old”.

“Hollywood celebrities say, ‘Oh, well, JD Vance, what if your daughter suffered fertility problems?’” Vance said.

“She had fertility problems, as I said in that speech, I would try everything I could to try to help her because I believe families and babies are a good thing.”

Paul Gigot, a Pulitzer Prize-winning conservative commentator, highlighted the political peril of selecting Vance as the VP pick and said that his defence of his comments was disingenuous.

“He wasn’t just attacking Democratic cat ladies, he was attacking people who, for some reason and not necessarily by choice, don’t have children,” he said on the Potomac Watch podcast.

“The overall ambience of this is I’m going to punish you if you don’t make my lifestyle choice.”

He said he “knows JD Vance a little” and called the Ohio senator “smug”.

“I think he can be condescending, but he’s not weird,” Gigot said.

“He’s just got some views that he thinks make him morally superior to you and me and that, I think, can be a political problem.”

Vance’s unpopularity problem has become such an issue for Trump’s camp that there is now swirling speculation that it could dump him from the ticket.