Sen. Jeff Flake said Wednesday that he will refuse to vote on dozens of President Donald Trump's judicial nominees until a bill protecting special counsel Robert Mueller's Russia probe comes to a vote in the Senate.
The Arizona Republican, who did not seek re-election and will retire at the end of his term, made the announcement on the Senate floor minutes after Senate Majority Leader Mitch McConnell, R-Ky., objected to his attempt to bring up the bill.
"I have informed the majority leader that I will not vote to advance any of the 21 judicial nominees pending in the Judiciary Committee, or vote to confirm the 32 judges awaiting a confirmation vote on the floor, until S. 2644 is brought to the full Senate for a vote," Flake said in the final sentence of the speech, referring to the Special Counsel Independence and Integrity Act.
"This bill is designed to do one thing: protect the integrity of the Special Counsel's investigation, and spare it of any interference from the executive branch, including from those who may themselves be subjects of the investigation," Flake said.
The departing senator's speech was itself a rhetorical defense of the special counsel, whose team is investigating Russian interference in the 2016 U.S. presidential election and possible coordination between Trump's campaign and the Kremlin.
"How such an investigation could be a cause of controversy is beyond me – surely we all recognize that it is essential to understand this new form of foreign aggression so that we might better defend America against such attacks in the future, right?" Flake said.
The firing of Attorney General Jeff Sessions, who had recused himself from overseeing Mueller's investigation, proved to Flake that the president has the Russia probe in his crosshairs. Flake maintained his stated view that the appointment of Sessions' chief of staff, Matthew Whitaker, as acting attorney general was "improper," even after the Justice Department cleared Whitaker for the role earlier.
As he has done numerous times from the Senate floor, Flake also criticized Trump directly. This time, Flake ripped Trump for appearing at times "eager to accept [Russian President Vladimir] Putin's denials at face value" when it comes to the U.S. intelligence community's assessment that Russia interfered with the election in Trump's favor.
Flake promised that he and Sen. Chris Coons, D-Del., who has partnered with Flake in the effort, would raise the legislation "again and again" until it is brought to a vote on the Senate floor.
Flake has voted with Trump 84 percent of the time, according to political data site FiveThirtyEight. When he departs the Senate in January, his seat will be filled by Democrat Kyrsten Sinema, who defeated Republican Martha McSally in a tightly contested election.
A spokeswoman for McConnell did not immediately respond to CNBC's request for comment. A spokesman for Senate Judiciary Committee Chairman Chuck Grassley, R-Iowa, also did not immediately respond.
Flake's vote is crucial for the nominees currently moving through the Judiciary Committee, which comprises 11 Republicans and 10 Democrats. Republicans cannot lose Flake's vote if they want to advance those judges.
But if Flake is the only senator voting across party lines in the full Senate body, Vice President Mike Pence will be able to cast the tie-breaker vote and push those nominees through.