Donald Trump is trouncing the rest of the Republican field with support for his main challenger, Ron DeSantis, falling by half, a new poll has found.

Despite facing 91 felony indictments, the former president appears unstoppable, forcing his opponents to rethink their tactics in the face of the Trump juggernaut.

Candidates who have avoided attacking Mr Trump out of fear of alienating the Republican base are reportedly now ready to do so.

They are also expected to step up campaigning in early voting states like New Hampshire and Iowa in the hope of slowing his momentum.

There is growing speculation that Mr Trump’s candidacy could face a legal challenge under the US 14th amendment, which disqualifies anyone who has “engaged in insurrection or rebellion against the United States” from seeking public office.

The Wall Street Journal poll, which gives the ex-president support from 59 per cent of Republican primary voters, an 11 per cent increase since April, underpins the growing desperation of Mr Trump’s opponents.

GOP voters overwhelmingly thought that the four criminal cases against Mr Trump lacked merit, with around half saying they had fuelled their support for him.

Some 78 per cent of voters said that Mr Trump’s efforts to overturn the 2020 election were legitimate attempts to ensure an accurate vote.

According to The Wall Street Journal, the former president’s lead over Mr DeSantis has nearly doubled to 46 per cent.

However, this is a reflection of the hemorrhaging of support for the Florida governor which has slumped from 24 per cent in April to only 13 per cent, five points ahead of Nikki Haley, the former South Carolina governor.

Vivek Ramaswamy, a Tech tycoon and political newcomer, is also threatening Mr DeSantis’s status as the only viable alternative to Mr Trump.

This has forced the DeSantis campaign to pivot and try to halt Mr Ramaswamy’s momentum, according to Politico.

Learn more about the candidates

Click to explore in-depth profiles of the presidential hopefuls

Republicans

Donald Trump

Former US President

Ron DeSantis

Florida Governor

Mike Pence

Former Vice President

Nikki Haley

Former US Ambassador

Vivek Ramaswamy

Health entrepreneur & venture capitalist

Chris Christie

Former New Jersey Governor

Asa Hutchinson

Former Arkansas Governor

Tim Scott

US Senator for South Carolina

Doug Burgum

North Dakota Governor

Francis Suarez

Miami Mayor

Will Hurd

Former CIA spy & former Texas congressman

Larry Elder

Political commentator

Perry Johnson

Entrepreneur & author

Democrats

Joe Biden

Incumbent US President

Robert F Kennedy Jr

Lawyer & activist

Marianne Williamson

Author & motivational speaker

Green Party

Cornel West

Philosopher & activist

Never Back Down, the super PAC supporting Mr DeSantis, is digging deep into Mr Ramaswamy’s past hoping to find damaging material.

On Sunday, Mr Ramaswamy, who has been Mr Trump’s staunchest supporter among the Republican hopefuls appeared to be putting some distance between himself and the former president.

While continuing to oppose the indictments, he questioned Mr Trump’s behaviour on Jan 6 2022.

The slim political hope of derailing Mr Trump rests in Iowa and New Hampshire, where the polls suggest more voters are willing to consider an alternative.

In Iowa, 72 per per cent of caucus-goers were either supporting other candidates or at least willing to consider doing so, even though Mr Trump leads the field with 42 per cent.

‘Only way’ to beat Trump

Meanwhile, internal polling by an unnamed rival candidate suggests Mr Trump’s bedrock support is somewhere between 28 and 33 per cent.

“The data does show some bright lights. In the early states, Trump polls at least 10 points below his national numbers,” said Chris Sununu, the Republican governor of New Hampshire and a critic of Mr Trump.

“There is still a lot more work to do, but there is plenty of time to do it.”

Chris Galdieri, professor of politics at Saint Anselm College in New Hampshire, believes this is the one remaining hope for Mr Trump’s rivals.

“I think that is the only way for somebody to beat Trump. In Iowa, Trump lost to Ted Cruz in 2016 and New Hampshire is the home of the Yankee Never Trumpers,” he told The Telegraph.

“Despite Trump’s name recognition, their hope is there might be a way of outhustling him with a lot of town halls and sending out a million flyers.

‌“I think it is unlikely, but that is their only hope. If Trump wins New Hampshire, South Carolina and Iowa, then there is nothing Nikki Haley and Ron DeSantis can do.”

The only other route is through the courts, with Mr Trump’s opponents seizing on the opinion of two conservative legal scholars – William Baude and Michael Stokes Paulsen – that the former president is disqualified from running under the 14th amendment.

Legal challenges have been filed and several secretaries of state are reportedly privately discussing the implications of the clause.

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