President Trump’s Twitter attack on federal Judge James L. Robart is driving a wedge between Trump and Republicans who argue that the President’s rhetoric undermines the independence of the judiciary, a co-equal branch of our government.

Trump lashed out at Robart as a “so-called judge” on Saturday following the judge’s order at least temporarily blocking enforcement on a presidential decree barring admission to the U.S. of travelers from seven African and Middle Eastern nations.

The barrage of Tweets continued on Sunday. “Just cannot believe a judge would put our country in such peril,” the President wrote. “If something happens blame him and court system. People pouring in. Bad!”

“It’s best not to single out judges,” Senate Majority Leader Mitch McConnell told a national audience on CNN on Sunday. “We all get disappointed from time to time. I think it is best to avoid criticizing them individually.”

Talk show host and former Congressman Joe Scarborough, usually a Trump ally, went after the President hard in a Washington Post op-ed. “When a president tweets insults at a Hollywood star, the dignity of his office is tarnished. When a commander in chief uses Twitter to attack a loyal military ally, America’s friends across the globe become unsettled. But when a president uses social media to question the legitimacy of a federal judge following an inconvenient (and temporary) outcome, that is simply unacceptable. From Marbury v. Madison to United States v. Nixon, our federal courts’ power to interpret the Constitution has been sacrosanct.”

The President’s attack on Judge Robart also appears certain to be an issue in the upcoming Senate hearings on Judge Neil Gorsuch, Trump’s nominee for the Supreme Court.

Senate Democratic Leader Charles Schumer, D-NY, served notice Saturday that in the wake of the President’s unusual challenge to the judge Democrats will press Gorsuch on his independence from the President and administration policies.

“With each action testing the Constitution, and each personal attack on a judge, President Trump raises the bar even higher for Judge Gorsuch’s nomination,” Schumer said in a prepared statement.

Ron Klain, a prominent Democratic lawyer in the administrations of former President’s Barack Obama and Bill Clinton, Tweeted that “The first question at Judge Gorsuch’s confirmation hearing should be whether he condones this disparagement of a fellow federal judge.”

Judge Robart, who is based in Seattle, was appointed to the bench by former President George W. Bush and confirmed 99-0 by the Senate in 2004.

Vice President Mike Pence will lead the Trump administration’s investigation of alleged voter fraud in last year’s election, the President announced on Saturday; actual evidence of voter fraud remains all-but-nonexistent however, and it’s unclear who else might be part of the investigation.

Dans un pre-Super Bowl interview with Fox News talking head Bill O’Reilly, Trump seemed to back away slightly from claims that up to 5 million people voted illegally last fall.

“It doesn’t have to do with the vote. It has to do with the registration,” Trump said. “And when you look at the registration, and you see dead people that have voted, when you see people that are registered in two states — and that voted in two states — when you see other things, when you see illegals, people that are not citizens and they are on the registration rolls.”

Registration records are maintained by state governments, which administer federal and state elections. Because Americans frequently move from state-to-state and are required to re-register in every locality, duplicate records are common and are neither illegal nor evidence of fraud. The same is true of registration records for people who are deceased.

Numerous studies, led by Democrats, Republicans and independent researchers, have concluded that actual fraud is extremely rare in U.S. elections.

GOP Senate Leader Mitch McConnell, R-KY, asserted Sunday that any investigation of duplicate or false registrations should be left to state governments. “There’s no evidence that (fraud) occurred in such a significant number that would have changed the presidential election, and I don’t think we ought to spend any federal money investigating that,” he said.

The Senate is expected to split 50-50 on the President’s nomination of Betsy DeVos to serve as Secretary of Education, forcing Vice President Mike Pence to cast his first tie-breaking vote.

If finally confirmed, DeVos will be the first Cabinet secretary to require a vice presidential vote to gain office. Her inexperience and apparent lack of information about public education and her uncertain answers to a variety of questions from senators during her confirmation hearings has fueled a torrent of letters, emails, phone calls and social media attacks on DeVos.

Two Republican senators, Susan Collins of Maine and Lisa Murkowski of Alaska, announced last week that they will vote No on DeVos, joining what appears to be unanimous opposition from the Senate’s 46 Democrats and two independents who caucus with the Democrats. A vote had been expected today but Democrats appear to have forced a delay until Tuesday.