3 Senate Republicans vow to block Feinstein's Judiciary replacement

At least three Republican senators have said they will not support a move to temporarily replace Sen. Dianne Feinstein, D-Calif., on the Senate Judiciary Committee -- saying they wouldn't want to help Democrats advance President Joe Biden's agenda.

On Monday afternoon, Sen. John Cornyn, R-Texas, who sits on the committee, became the most recent Republican to voice his opposition to temporarily replacing Feinstein while she recovers at home from having shingles, signaling an uphill battle Senate Democrats face in securing a replacement.

"Never, not once, have we allowed temporary substitutes on committees, and now is not the time to start. Republicans are not going to break this precedent in order to bail out Senator Schumer or the Biden administration's most controversial nominees," Cornyn, a senior Republican close to Senate Minority Leader Mitch McConnell, claimed. "Senator Feinstein has been a mainstay of this body for more than three decades, and I hope to see her back in these halls soon. But until then, President Biden's most controversial parts partisan judicial nominees will have to wait," he added later.

With lawmakers returning to Washington on Monday from a two-week recess, Senate Democrats were poised to find a senator to temporarily replace Feinstein on the committee, the first step in freeing up a log-jam of politically important judicial nominations accumulated in her absence.

The Senate Judiciary Committee, where Democrats hold a mere one-seat majority, as they do in the full chamber, is the first stop for the president's judicial nominations. With lifetime appointments, judges can deeply shape how the nation's laws are interpreted.

After the 89-year-old senator said last week she was extending her already six-week absence from the Senate due to complications related to having shingles, Senate Majority Leader Chuck Schumer said he would grant her request to find another Democratic senator to temporarily serve in her place.

But Republicans may not allow for what's typically a routine move to go forward smoothly.

Any hopes to pass Feinstein's replacement through a unanimous consent vote were quashed over the weekend, when Sen. Tom Cotton, R-Ark., a committee member tweeted an op-ed questioning why Republicans would cooperate with Feinstein's ask, and said, "Republicans should not assist Democrats in confirming Joe Biden's most radical nominees to the courts."

Sen. Marsha Blackburn, R-Tenn., also a committee member, joined Cotton on Monday to argue that helping Schumer to replace Feinstein would amount to helping Democrats "pack the court with activist judges."

"I will not go along with Chuck Schumer's plan to replace Senator Feinstein on the Judiciary Committee and pack the court with activist judges," Blackburn tweeted on Monday. "Joe Biden wants the Senate to rubber stamp his unqualified and controversial judges to radically transform America."

It will now take at least 60 votes to pass the resolution required to temporarily replace Feinstein on the high-stakes committee, meaning at least 10 Republicans need to join Democrats in the 51-49 chamber under narrow Democratic control.

And with Cornyn adding his voice, it's unclear how much other opposition Democrats might face.

Schumer, for his part, didn't appear concerned with the objectors when he returned to the Capitol on Monday and said he planned to bring the matter to the floor later this week.

"We should have a temporary replacement until she returns and we're hopeful Republicans will join us on that," he told reporters. "It's the only right and fair thing to do."

Sen. Amy Klobuchar, D-Minn., acknowledged on ABC's "This Week" that Feinstein's absence could become a bigger problem for Democrats if it extends into votes on raising the debt ceiling, for instance.

"If this goes on month after month after month, then she's gonna have to make a decision with her family and her friends about what her future holds, because this isn't just about California; it's also about the nation," Klobuchar said. "So it's going to become an issue as the months go by. But I'm taking her at her word that she's going to return."

Despite at least two House Democrats calling on her to resign, lawmakers might not have to wait much longer for the oldest member of Congress to return.

"I spoke to Senator Feinstein, just a few days ago," Schumer said. "She believes she will return soon."

Until she does, Republican Sen. Chuck Grassley of Iowa, also 89 but three months shy of Feinstein's age, has the distinction of being the oldest lawmaker in Washington -- as of Monday.

ABC News' Trish Turner and Lalee Ibssa contributed to this report.