WASHINGTON — As the Senate prepares to return to Washington next week, the focus will be not on the coronavirus but instead on judicial nominations that have long been a priority for Senate Majority Leader Mitch McConnell — one that has been sidelined in recent weeks as Congress has scrambled to react to the pandemic.

McConnell's decision to bring the Senate back to Washington with no immediate plans to take up additional coronavirus relief legislation has left some members uneasy about traveling when stay-at-home orders remain intact in most states and the congressional attending physician recommends that Congress stay away for now.

But McConnell, R-Ky., has said the pandemic isn't going to get in the way of confirming judges, telling a conservative radio host recently that his "motto" for this year is "leave no vacancy behind."

And he is particularly focused on two controversial appeals court nominees who, if confirmed, would leave no more vacancies on the circuit court level.

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One of the nominees, U.S. District Judge Justin Walker of Kentucky, who is up for the D.C. Circuit Court of Appeals, is a McConnell protégé who clerked for then-Supreme Court Justice Anthony Kennedy and then-appeals judge Brett Kavanaugh. He was a vocal defender of Kavanaugh during Kavanaugh's Supreme Court confirmation hearings.

Walker's confirmation hearing in the Senate Judiciary Committee is slated for Tuesday, one of the first orders of business when the Senate returns, according to a Republican familiar with committee plans that haven't yet been officially announced.

Democrats are challenging McConnell's decision to reconvene next week. Minority Leader Chuck Schumer of New York sent a letter arguing that the Senate should come back only to consider coronavirus legislation and to conduct oversight of the rescue programs.

"If we are going to be in D.C. with the coronavirus raging, it is critically important that we continue and actually ramp up our messaging and activities on the oversight front," Schumer told Democratic senators on a conference call Tuesday, according to an aide on the call. "We must hold the administration accountable for the mistakes they are making on the small-business program, hospitals, testing and more."

Despite earlier indications to the contrary, the House reversed course and announced Tuesday that it won't return next week, pointing to recommendations from Congress' attending physician.

"It's a dangerous move that achieves nothing," a Democratic aide said of McConnell's decision to call the Senate back. "It would be one thing if this were necessary to addressing the crisis and help people, but it's not about that."

Privately, even some Senate Republicans are voicing frustration with McConnell's bringing the Senate back with only judges on the immediate agenda.

McConnell has defended his decision to return, saying that despite the House not coming back into session, the two chambers can still begin discussing the next phase of coronavirus legislation.

“We’re gonna honor our Constitutional duty to the American people and conduct critical business, and we’re gonna do it in person,” McConnell said to Brian Kilmeade on Fox News Radio Wednesday. “We’re not gonna sit on the sidelines during this period in the Senate. And we’re willing to discuss with the House, even if they’re not around, we’re willing to discuss the way forward, as I’ve already outlined, provided, we have protections for the brave people who have been on the frontlines.”

McConnell adjourned the Senate for a long weekend in mid-March and attended an event for Walker in Kentucky while the Senate was waiting for the second phase of coronavirus relief legislation to arrive from the House.

Judicial nominations have been one of McConnell's top priorities over the first three years of the Trump administration.

He has helped usher through the confirmations of a record number of judges — 193 — during Trump's presidency, including two Supreme Court justices and 51 circuit judges. By comparison, the Senate confirmed only 55 circuit judges in all eight years of Barack Obama's presidency.

McConnell hasn't just helped to reshape the judiciary with conservative lifetime appointments. It has also been a successful political tactic — he has credited his decision not to hold hearings on an Obama Supreme Court nominee, Merrick Garland, with Trump's victory in 2016.

And he is pledging not to let up.

"As soon as we get back in session, we'll start confirming judges again," McConnell told conservative radio host Hugh Hewitt last week. "My motto for the year is 'leave no vacancy behind.' That hasn't changed. The pandemic will not prevent us from achieving that goal."

Hewitt, who has rallied around the president largely because of the judiciary, responded by saying, "That's music to my ears."

McConnell's commitment to judges amid a pandemic comes as recent polling and fundraising numbers show that some Republican senators in swing states have difficult roads to re-election.

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Keeping a focus on the courts is a proven strategy to unite and motivate the Republican base, including in Kentucky, where McConnell is also up for re-election.

"I think any time Republicans are talking about judges or pushing through judicial nominations, it's a win for them," said Garrett Ventry, a former Republican spokesman for the Senate Judiciary Committee.

The D.C. Circuit, for which Walker is nominated, is a crucial bench that is not only a breeding ground for the Supreme Court but is also the court that hears disputes between the branches of government, including congressional lawsuits against the president.

Walker, who was barely confirmed for the Western District of Kentucky along party lines in a 50-41 vote less than a year ago, was deemed "unqualified" by the American Bar Association because of his lack of experience, but the group added that it saw no concerns with his temperament or integrity.

In an interview with the "PBS NewsHour" on Tuesday, Schumer noted that background while criticizing McConnell.

"It seems what he wants to do," Schumer said, "is have us vote for, have hearings on a judge who is sort of a crony of his, someone who used to work on his staff who was rated unqualified by the ABA. People are hurting. People are dying. We ought to use this time to exercise our oversight authority."

Democrats and liberal groups have also opposed the confirmation of Cory Wilson for the 5th Circuit, which includes Texas. If Wilson and Walker are confirmed, there will be no more vacancies on the circuit courts.