Walz and Vance face off in only vice presidential debate

Democrat Tim Walz and Republican JD Vance, two sons of America's Midwestern heartland with deeply opposing views on the issues facing the US, shook hands ahead of the only vice presidential debate of the 5 November election.

Mr Walz, 60, the liberal governor of Minnesota and a former high school teacher, and Mr Vance, 40, a bestselling author and conservative firebrand senator from Ohio, are expected to clash early and often, with each trying to land a lasting blow in an event that has historically had little measurable impact on White House campaigns.

Aides to the two men predicted fireworks during the 90-minute televised debate at the CBS Broadcast Center in New York, as they defend themselves and speak up for the candidates at the top of each ticket, Democratic Vice President Kamala Harris and Republican former President Donald Trump.

Mr Walz has called his Republican opponents "weird," and Mr Vance came under fire for past comments disparaging some Democrats as "childless cat ladies".

Ms Harris and Mr Trump are expected to watch the debate, which began at 9pm (2am Irish time).

Mr Trump said he would offer a play-by-play commentary of the event on social media.

Ms Harris was widely viewed as the winner of her sole debate with Mr Trump on 10 September in Philadelphia, which was watched by an estimated 67 million people.

That debate did little to change the trajectory of an extremely close election battle.

While Ms Harris has edged ahead in national polls, most surveys show voters remain fairly evenly divided in the seven states that will decide the November election.

Political analysts say vice presidential debates can be fiery but generally do not alter the outcome of an election.

That said, even a slight shift in public opinion could prove decisive with the race on a razor's edge five weeks before election day.

The main takeaway from the last vice presidential debate, the 2020 encounter between then-Senator Harris and then-Vice President Mike Pence, was a fly that landed on Mr Pence's head unbeknownst to Mr Pence himself.

With no more debates planned, the stand-off allows Mr Walz and Mr Vance to make closing arguments on behalf of their campaigns -just as early voting ramps up across the country.

Mr Walz, who has sought to cultivate a homespun image as a former high school football coach, is expected to get Mr Vance to defend his 2021 comments criticising Ms Harris and other Democrats as "a bunch of childless cat ladies who are miserable at their own lives".

Mr Walz is also likely to go after Mr Vance for spreading a fictional story of Haitian immigrants eating household pets in Springfield, Ohio, a false claim that Mr Trump has repeated and that local officials say has drawn bomb threats.

The Democrat will seek to introduce himself to US voters who may not be familiar with him, while aiming to keep the conversation focused on Ms Harris' agenda, said an adviser to Mr Walz who asked to remain anonymous to discuss strategy.

Mr Trump adviser's said Mr Vance will try to force Mr Walz to defend the Biden-Harris administration's policies on immigration and the economy, as well his own handling of the riots in Minneapolis in 2020 after the death of George Floyd, black man, at the hands of a white policeman.

Mr Vance will also bring up questions about Mr Walz's military service, said Tom Behrends, a retired command sergeant major who joined a Trump campaign call about the debate.

Republicans have accused Mr Walz of exaggerating his final rank in the Army National Guard, where he served for 24 years.

Mr Walz has in the past described himself as a retired command sergeant major, one of the highest non-commissioned officer positions in the army.

While he achieved that rank, he did not meet the requirements to retire with that title.

The Harris campaign said Mr Walz "misspoke" in 2018 during his gubernatorial campaign in Minnesota when he referred to "weapons of war, that I carried in war".

Mr Walz was never deployed to a war zone.

Mr Vance is a former Marine who served as a military journalist.

He was deployed to Iraq but never saw combat.

Earlier, Minnesota Public Radio reported that Mr Walz was not in China during the 1989 Tiananmen Square crackdown as he has previously claimed but traveled there months later, another misstatement likely to draw Mr Vance's fire.

Despite Mr Vance's having written "Hillbilly Elegy," a popular 2016 memoir, US voters have a negative view of him, Reuters/Ipsos polling shows, with 51% of registered voters saying they view him unfavourably, compared with 39% who view him favourably.

Meanwhile Mr Walz was viewed favourably by 44% of registered voters, with 43% reporting an unfavourable view in the 20-23 September poll.