The Republican-led House of Representatives has failed in a knife-edge vote to fire Homeland Security Secretary Alejandro Mayorkas over the migrant crisis at the US-Mexico border.
Four Republicans broke ranks and joined all Democrats in a 216-214 vote.
Opponents of US President Joe Biden blame Mr Mayorgas for increasing illegal immigration across the US border.
Border security is becoming a major political issue in the 2024 elections.
Ken Buck of Colorado, Tom McClintock of California and Mike Gallagher of Wisconsin, three Republican abstentions, voted no Tuesday evening.
Fourth, Blake Moore of Utah switched his vote from yes to no as a practical maneuver to ensure Republicans would bring back the resolution at their election time.
A big drama ensued when Al Green, a Democrat from Texas, was wheeled across the floor wearing hospital scrubs for refusing to vote. He was in the emergency room for surgery.
Even if the House had passed the vote, Mr Mayorkas would not have been found guilty by the Democratic-controlled Senate.
Impeachment proceedings were initiated by Georgia Republican Marjorie Taylor Green, who said she would try again after the vote.
“My colleagues who voted no, I think they will hear from their constituents,” he told reporters outside the Capitol.
Looking ahead, House Speaker Mike Johnson told reporters Wednesday that Republicans are confident “we'll get it done in the next round.”
“We have a razor-thin margin and every vote counts — sometimes when you're counting votes and people show up when they're least expected in the building that changes the equation,” he said, referring to Congressman Green's last-minute appearance. .
“You see the messy sausage playing out the process of democracy,” he said.
“We must hold the secretary of Homeland Security accountable. Mayorgas must be held accountable. The Biden administration must be held accountable, and we will carry out those articles of impeachment.”
Raj Shah, a spokesman for House Speaker Johnson, posted on X that Republicans would try to impeach Mr. Mayorkas again.
Several congressional Republicans said the setback would have no impact on their separate impeachment inquiry into President Biden.
Signs of discontent over the mayorgas vote had already surfaced in the party rank and file earlier in the day.
Mr McClintock said on Tuesday morning he would vote against the impeachment because the articles “fail to identify the impeachable offense committed by Mayorkas” and “stretch and distort the Constitution”.
Impeachment is the first step in the removal of a federal official for felony or misdemeanor, as set forth in the U.S. Constitution.
It needs a simple majority in the House and a two-thirds majority in the Senate to pass. Democrats currently control the upper chamber.
The last cabinet secretary to be sacked was Secretary of War William Belknap in 1876, although he resigned shortly before the referendum.
A spokesperson for the Department of Homeland Security said in a statement: “This baseless allegation should not have moved forward; it faces bipartisan opposition and legal experts firmly say it is unconstitutional.
“If House Republicans are serious about border security, they need to drop these political games,” he added.
House Republicans held two hearings in January accusing Mr. Mayorkas of failing to implement immigration policies and lying to lawmakers about whether the southern border was secure.
The secretary did not testify during the hearings.
Before Tuesday's vote, Jim McGovern, Democrat of Massachusetts, said Republicans “want to create chaos, they want to create chaos, and they want to create a campaign problem for Donald Trump going into the next election.”
But Chip Roy, Republican of Texas, argued that Mr Mayorgas had failed to enforce US immigration law “in a way that has led directly to the death of US citizens and immigrants”.
A January poll by CBS – the BBC's American affiliate, found that 63% of Americans favor “tough” border policies.
More than 6.3 million immigrants are known to have entered the US illegally since Mr Biden took office in 2021.
About 2.4 million Americans have been admitted, with the vast majority awaiting immigration court dates at which they can claim asylum. This system is very extensive and can take years.
This week, a bipartisan group of U.S. senators announced a bill that would step up border enforcement efforts and provide additional aid to Ukraine and Israel.
House Republicans have rejected the bill outright.
After Tuesday's impeachment vote, the House considered a separate Republican bill that would have given Israel $17.6bn (£14bn), but that also failed to pass.