Republican and Democratic rivals clash in fiery Fox News event filled with personal insults.

The matchup between DeSantis, the governor of Florida, and Newsom, an ally of President Joe Biden who is widely expected to mount a future White House bid, was filled with policy clashes and personal insults.

DeSantis labelled Newsom a liar in charge of a failing state, while Newsom ridiculed his Florida rival as a bully who is badly losing to Republican presidential rival Donald Trump.

“When are you going to drop out and at least give Nikki Haley a shot to take down Donald Trump,” said Newsom, 56, referring to the former South Carolina governor who has beaten DeSantis in some polls as the preferred alternative to Trump.

DeSantis labelled Newsom a “slick, slippery politician whose state is failing”.

“People are leaving California in droves,” he said.

The host, the Fox News Channel, touted the 90-minute event as “The Great Red vs Blue State Debate”.

The debate, hosted by Sean Hannity, was held in a television studio with no audience in Georgia, a key swing state.

As leaders of two of the three most populous states, DeSantis and Newsom have spent much of the past year attacking each other’s policy choices and leadership styles from afar. But on Thursday night, they got their first chance to challenge each other on the same national stage.

The two participants, standing at podiums alone onstage, talked over each other often.

DeSantis, who was elected to his second and final term as governor in November 2022, is grasping for momentum in a 2024 campaign in which Trump remains the overwhelming frontrunner.

Newsom, California’s term-limited Democratic governor, has positioned himself to seek the presidency some day, but like the rest of his party’s most ambitious leaders, he declined to challenge Biden for the Democratic nomination in 2024.