WASHINGTON – Congressional Democrats on Friday demanded that lawmakers act to protect special counsel Robert Mueller after revelations President Donald Trump sought to oust him last summer from overseeing the probe into Russian meddling in the 2016 election.

Several Democrats and one moderate Republican called for votes on Senate legislation that would prevent presidents from firing special counsels unless a panel of three federal judges agreed with the move, citing the revelations that Trump came close to pushing out Mueller last June.

The president backed off only after White House counsel Donald McGahn threatened to quit, according to two people familiar with the episode.

Republican leaders show no new urgency to address the matter, saying that the president's threats are isolated and in the past.

“If these latest reports are true, it seems to me that they show the president listened to good advice from his advisers,” Sen. Charles Grassley, R-Iowa, who chairs the Judiciary Committee with jurisdiction over any special-counsel bill, said Friday. “Based on his statements from the last couple weeks, he and his lawyers appear to be cooperating with Mueller.”

Sens. Lindsey Graham, R-S.C., and Thom Tillis, R-N.C., responding to rumors in the summer that Trump might fire Mueller, each advanced legislation that would involve a panel of federal judges in any decision to end a special counsel's tenure.

Graham's bill, co-written by Sen. Cory Booker, D-N.J., and other Democrats, would require a three-judge panel to approve a presidential order to fire a special counsel. Tillis' bill, written with Sen. Christopher Coons, D-Del., would allow a fired special counsel to appeal the president's decision to a panel of judges, to avoid trampling the president's executive authority.

Lawmakers have thus far not been able to reconcile the two bills and satisfy Grassley, who says he has “constitutional concerns” with the legislation and will address only one bill in committee.

Moderate Republican Rep. Charlie Dent of Pennsylvania predicted that the news that McGahn “prevented an Archibald Cox moment” – a reference to the prosecutor whose firing President Richard Nixon ordered during the Watergate scandal – would increase pressure to “protect Mueller.” But Republicans remain unruffled even as the president is expected to be interviewed by Mueller's team.

“The timeline is critical here,” Tillis spokesman Daniel Keylin said Friday, noting that Trump sought to fire Mueller in June and the bills were introduced in August.

Since their introduction, Keylin said, “the chatter that the administration is considering removing special counsel Mueller has completely come to a halt.”

Democrats, frustrated by what they see as Republican recalcitrance, openly accuse the GOP of abetting an all-out assault on the special counsel and the federal law enforcement agencies assisting him.

“Republicans in Congress have been co-opted into participating and amplifying these attacks” against the Justice Department and the FBI, said Rep. Jerrold Nadler of New York, the ranking Democrat on the House Judiciary Committee. The GOP, he added, is complicit in “sham investigations” of Trump's former political opponent Hillary Clinton to distract from the inquiries into the president's alleged ties to Russia.

This week's revelations about Trump's attempts to oust Mueller, first reported by the New York Times, came as the special counsel has been deepening his investigation into potential obstruction of justice, according to people who have interacted with his team.

Asked about the report Friday at the annual World Economic Forum in Davos, Switzerland, Trump declared it “fake news.”