Washington (AFP) - Joe Biden's immigration chief narrowly escaped impeachment over the US border crisis Tuesday, in a party-line vote dismissed by Democrats as a political stunt ahead of a presidential election expected to feature immigration as a major issue.

The failed rebuke was led by hardline Republicans in the House of Representatives who have been targeting Homeland Security Secretary Alejandro Mayorkas for months over a surge in illegal entries across the southern border.

Republicans had been sweating on what was expected to be a close vote, and so it proved -- as three members of the party sided with Democrats in a vote that ended 216-214 in Mayorkas's favor.

Impeachment is the political equivalent of an indictment and Mayorkas would have faced the prospect of a trial in the Senate, although he would have been acquitted by the Democratic-led upper chamber and allowed to keep his job.

The House -- which had only impeached one other cabinet official in its history, Secretary of War William Belknap in 1876 -- took a single vote on two articles accusing Mayorkas of failure to enforce the law and of lying to Congress.

Republicans command a narrow majority in the lower chamber and two conservatives jangled nerves in the leadership team as they announced their opposition to the impeachment ahead of the vote. They were joined by a surprise third dissenter as the vote played out, killing the impeachment drive.

"The failure of the Biden administration to rein in an open border is a national disgrace and will be a stain on his presidential legacy," Colorado's Ken Buck, one of the Republican rebels, wrote in an op-ed for congressional newspaper The Hill. 

"However, the truth is that this is a policy disagreement masked as an impeachment." 

California's Tom McClintock, another dissenter, released a 10-page memo accusing his party of failing to identify an impeachable "high crime or misdemeanor."  

'Political stunt'

The impeachment resolution accused Mayorkas of "willful and systemic refusal to comply with the law" on securing America's borders and charged him with "breach of public trust."

"Impeaching a cabinet member without any evidence of high crimes or misdemeanors? That is the breach of public trust here," said Minority Whip Katherine Clark. 

The vote came amid a showdown between the House and the Senate over curbing a surge in illegal immigration that led to a record 10,000 apprehensions a day at the border in December. 

House Republicans have been accused of acting in bad faith over the Mayorkas impeachment after coming out against a bipartisan Senate deal that would impose the toughest asylum and border policies in decades.

The Republicans had initially pushed for the measures as a condition of providing aid for Ukraine.

But a trickle of opposition to the bill turned into a major backlash as former president Donald Trump, who is seeking reelection and sees immigration as one of Biden's top vulnerabilities, warned his party to oppose it.

Democratic Leader Hakeem Jeffries accused Republicans of pandering to Trump's White House ambitions when they could be working to fix the "broken immigration system." 

"Instead, what you have to offer the American people is this sham impeachment, this political stunt, this waste of time. But you will not fool the American people," he said.

House Democrats voted in unison against the impeachment, which was also vehemently opposed by the White House and the Department of Homeland Security (DHS).

"I think it is baseless. I think it's a political process, and I am not engaged in politics," Mayorkas told The New York Times Magazine as part of a media charm offensive ahead of the vote.

He railed against Republicans' "accusatory, rather than solution-focused" politics in an interview in The Washington Post.