US President Donald Trump has warned that his policies will be "violently" overturned if the Democrats win November's mid-term elections.
He told Evangelical leaders that the vote was a "referendum" on freedom of speech and religion, and that these were threatened by "violent people".
He appealed to conservative Christian groups for help, saying they were one vote away from "losing everything".
Mid-term elections are widely seen as a test of the president's popularity.
Mr Trump has been battling negative publicity after his ex-lawyer and former campaign chief were convicted earlier this month.
An audio recording of Mr Trump's closed-door meeting with Evangelical leaders at the White House was leaked to US media.
During the meeting, Mr Trump said the mid-term elections were not just a referendum on him but also "on your religion, it's a referendum on free speech and the First Amendment [guaranteeing basic freedoms]".
"It's not a question of like or dislike, it's a question that they will overturn everything that we've done and they will do it quickly and violently. And violently. There is violence. When you look at Antifa - these are violent people," he said.
Antifa - short for anti-fascist - refers to groups of far-left protesters who fight far-right ideology and regularly clash with far-right demonstrators.
The US president has previously criticised left-wing groups, infamously saying that there had been violence on "many sides" after a white nationalist killed a left-wing demonstrator at a white nationalist protest in Charlottesville last year.
Urging the Evangelical leaders to use their influence to swing voters, Mr Trump told them they had "tremendous power".
"In this room, you have people who preach to almost 200 million people. Depending on which Sunday we're talking about," he said.
"Little thing: Merry Christmas, right? You couldn't say 'Merry Christmas'," he added, according to US media reports.
Two of those who heard Mr Trump speak downplayed the remarks, according to a series of tweets by Sarah McCammon, a reporter from National Public Radio (NPR).
"Nobody walked out of there thinking that the Democrats were going to shoot us all," she quoted Jerry Falwell Jr as saying.
.@ralphreed said Trump didn’t warn of violence in his estimation: “He said if the Democrats take the House there will be virulent opposition to his agenda. He said some of those groups on the left incite and advocate violence and mentioned Antifa.”— Sarah McCammon NPR (@sarahmccammon) August 29, 2018
What's at stake in the midterms?
President Donald Trump himself is not up for re-election, but his ability to govern in the final two years of his term will hinge upon the 6 November outcome.
All 435 members of the House of Representatives, 35 seats in the 100-member Senate and 36 out of 50 state governors, along with many state and local offices, are up for election.
Republicans currently hold sway in both chambers of Congress and the White House. But some Democrats have been predicting a "blue wave".
On Tuesday a left-wing Democratic candidate beat better-funded centrist challengers to win his party's primary contest and will stand against Mr Trump's favoured candidate.
Andrew Gillum, who is currently mayor of Tallahassee, will oppose Ron DeSantis. If elected, Mr Gillum would be Florida's first black governor.