Corrected 10 p.m. | As President Donald Trump emerged from Walter Reed National Military Medical Center on Monday evening, Senate Republicans were continuing to operate on a timeline that would allow them to confirm Amy Coney Barrett to the Supreme Court — even as they faced cases of COVID-19 within their ranks that may have started at the White House.

Sen. Ron Johnson, a Wisconsin Republican who has tested positive for coronavirus, said in a Monday radio interview that he was prepared to return to the Capitol to vote to confirm Barrett even if he tests positive shortly before the vote. Doing so would violate Centers for Disease Control and Prevention isolation guidelines, as well as the District of Columbia’s virus protocols, although there is little to no enforcement of such.

“I’ve already told leadership I’ll go in a moon suit,” Johnson told KHOW radio. “People can be fairly confident that Mitch McConnell is dedicated to holding a vote,” he said of the Senate majority leader.

Johnson even floated the idea of holding the vote electronically, although the Homeland Security and Governmental Affairs chairman suggested that might be too far-fetched for the Senate since it would require rules changes beforehand.

Judiciary Chairman Lindsey Graham of South Carolina has already announced that the Senate confirmation hearings for Barrett will kick off as scheduled on Oct. 12, even though McConnell was able to announce an agreement Monday on the Senate floor effectively scrapping all floor business until at least Oct. 19. Lawmakers would likely only return for floor votes if there is a deal on additional COVID-19 relief.

“Across all our committees, we’ve had 150 hybrid hearings since the pandemic began. The Senate has used this format no fewer than 150 times,” McConnell said opening the Senate during a brief session Monday. “We have continued performing our constitutional duties while protecting health and safety during the pandemic.

“So whatever mix proves to be the right decision at this time next week, it will be completely consistent with the Committee’s own precedent, and with the ways committees across the Senate have adapted and done their work throughout this pandemic,” McConnell said.

But the circumstances of the last week demonstrate that in the midst of a global pandemic, plans require contingencies. When senators departed the Capitol last Thursday afternoon, they expected to have to return this week for votes to confirm several of Trump’s other judicial nominees — with Democrats opposing allowing the Senate to recess, which would prevent vulnerable Republicans from campaigning.

Since then, the president and first lady have tested positive for the coronavirus, with the president having been hospitalized at Walter Reed in Bethesda, Maryland, from Friday until Monday evening. It is unclear how many members or aides may have been exposed and under what circumstances last week, as more figures within the president’s inner circle are testing positive for the virus.

Physician to the President Sean Conley declined on Monday to say exactly when the president last received a negative test result, citing health privacy regulations under HIPAA, which can only make the contact tracing exercise more complicated at both ends of Pennsylvania Avenue. As a patient, Trump could have waived any HIPAA privacy concerns and allowed Conley to reveal information about test results or any other health information.

In the past week, Johnson received a positive test, as did Judiciary Committee Republican Sens. Mike Lee of Utah and Thom Tillis of North Carolina.

Johnson was not in attendance at the Rose Garden ceremony for the Barrett announcement on Sept. 26, but Lee and Tillis were. Other Republican senators at that event include Marsha Blackburn of Tennessee, Josh Hawley of Missouri, Ben Sasse and Deb Fischer of Nebraska, Michael D. Crapo of Idaho and Kelly Loeffler of Georgia. They have all tested negative since. A complete list of people at the event is not available.

The real challenges for the Senate GOP would arise if Judiciary Committee members were to become more seriously ill or if others need to enter self-quarantine because of exposure to COVID-19. That is because they have only a two-seat advantage over the Democrats on the committee and proxy votes are not allowed in the committee, if they would affect an outcome.

Graham has said every senator has the option of attending the hearings virtually. But any committee votes must be done in person. Democrats say the significance of a Supreme Court confirmation demands in-person attendance. That would also dovetail with their position that the hearings should be delayed until after the election.

Lee and Tillis are still isolating, as is Texas GOP Sen. Ted Cruz, who has tested negative but is isolating because of potential exposure. Those three, plus Blackburn, Hawley, Sasse and Crapo, are all on the Judiciary Committee.

There are procedural moves that McConnell could still make to bring the Barrett nomination to the floor, but that would put even more of a spotlight on the Republicans who dominate the list of most vulnerable incumbents this year.

Sen. Sheldon Whitehouse, a Rhode Island Democrat on the committee, noted that even the chairman himself is in a difficult race this year against Democrat Jaime Harrison.

“It could be asking a lot for Sen. Graham to come to Washington for this hearing, which will be a constant reminder of his 180 degree flip-flop,” Whitehouse said, referring to past comments by Graham that the Senate should not vote on a Supreme Court nominee during an election year, “instead of being home in South Carolina trying to salvage his reelection.”

Graham and other Republicans insist the circumstances are different with a GOP Senate majority and a Republican in the White House, but the fact is that the hearings will now play out amid heightened uncertainty of potential COVID-19 spread from the event where Barrett, a judge on the 7th U.S. Circuit Court of Appeals, was announced as the Supreme Court nominee by the president.

Graham has pointed to his advocacy for Trump’s judicial nominees as a key reason why he should be reelected.

“If you want conservative judges, I’m your only bet in this race,” Graham said during a Saturday debate with Harrison.

As McConnell previewed in a Saturday statement, the Senate will now be in pro forma session, with no business conducted, for the next two weeks.

Virginia Democratic Sen. Tim Kaine on Monday asked McConnell to modify his plan and to keep the Senate out until after Election Day, but McConnell objected. That keeps open the possibility that the Senate will vote on Barrett’s confirmation before the Nov. 3 election.

Kaine, who appeared to be filling the role of Minority Leader Charles E. Schumer during Monday’s brief session, tested positive for coronavirus antibodies in May. Schumer on Monday suggested that during the Barrett hearings, testing protocols should be implemented that more resemble those used by professional sports leagues.

“Every Senator and relevant staff must have negative tests on two consecutive days and have completed the appropriate quarantining period, and there should be mandatory testing every day of the hearing,” Schumer said in a statement.

Among the members of the Judiciary Committee are two lawmakers in their 80s, placing them in a high-risk group for COVID-19. Ranking Democrat Dianne Feinstein of California is 87. Former Judiciary Chairman Charles E. Grassley of Iowa is also 87. And, as the senior Republican in the chamber, Grassley is also Senate president pro tempore, who happens to be third in line to the presidency in the line of succession.

This report was corrected to state Sean Conley’s role in the administration and the day Mitch McConnell previewed a change in the Senate schedule.