WASHINGTON (2nd UPDATE) - Former U.S. Vice President Mike Pence formally launched his 2024 presidential campaign on Wednesday, taking a massive swipe at former President Donald Trump and pledging to turn the United States around by respecting the Constitution and conservative values.

Joining an increasingly crowded field of Republican candidates vying for the party's presidential nomination, Pence declared his challenge against his former boss Trump, the current front-runner, whom he served in the White House for four years through 2021.

Pence has become the first vice president in modern U.S. politics to run against his previous running mate.

"Today our party and our country need a leader that will appeal, as Lincoln said, to 'the better angels of our nature,'" Pence said in a video released in the morning ahead of a kickoff event in Iowa, the earliest U.S. state to vote in the party's nominating process.

I believe in the American people, and I have faith God is not done with America yet. Together, we can bring this Country back, and the best days for the Greatest Nation on Earth are yet to come! 🇺🇸 #Pence2024 pic.twitter.com/A8EkqgCDAm

— Mike Pence (@Mike_Pence) June 7, 2023

In a speech to his supporters at the event, Pence said that Trump had forced him to choose between the then-president and the Constitution in the wake of their 2020 election defeat, and underscored his decision to stand up for the rule of law.

"Anyone who puts themselves over the Constitution should never be president of the United States, and anyone who asks someone else to put them over the Constitution should never be president of the United States again," he said.

Since leaving office, Pence, a staunch conservative who also formerly served as an Indiana congressman and then governor, has distanced himself from Trump. In March, he made scathing comments about the former president's role in the attack on the U.S. Capitol in January 2021.

Pence, who turned 64 on Wednesday, said at the time that Trump's encouragement of rioters and his reckless words leading up to the attack "endangered my family and everyone at the Capitol that day," and that history will hold the 76-year-old former president "accountable."

Pence has sought to cast himself as a traditional conservative Republican in the model of former President Ronald Reagan. He is trying to draw support from backers of Trump, but is expected to face an uphill battle.

• Former VP Mike Pence announces Republican nomination bid

Among a pack of hopefuls seeking the Republican nomination, including former New Jersey Gov. Chris Christie, who entered the race on Tuesday, opinion polls have shown that only Trump and Florida Gov. Ron DeSantis, 44, have managed to reach double-digit support.

On Wednesday, North Dakota Gov. Doug Burgum also joined the Republican nomination race.

The Democratic Party, meanwhile, has fewer candidates for its nomination and President Joe Biden, who launched his re-election campaign in late April, has no major rivals so far. But polls have indicated that public support for the 80-year-old leader's bid for a second term is tepid, even among Democrats.

==Kyodo

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