Washington(CNN) Senators were stunned Tuesday when their colleague Sen. Jeff Flake, an Arizona Republican and occasional target of President Donald Trump's ire, walked onto the Senate floor, delivered a blistering speech on the state of the country's politics and announced he would no longer seek re-election for the Senate in 2018.
"It's a very sad day. He was a very good man and a very good senator," Sen. John Cornyn, the No. 2 Senate Republican, told reporters.
As Flake delivered his remarks on the Senate floor Tuesday, a handful of Republican and Democratic lawmakers sat, listening intently. Majority Leader Mitch McConnell turned to watch Flake on the floor. And, as Flake's speech concluded, some including Sens. John McCain of Arizona and Bob Corker of Tennessee gave Flake a standing ovation.
"It's been one of the great honors of my life to have the opportunity to serve with a man of integrity and honor and decency and commitment to not only Arizona, but the United States of America," McCain said on the Senate floor. "I have seen Jeff Flake stand up for what he believes in knowing full well that there would be a political price to pay."
But Flake's surprising announcement also caught his Democratic colleagues off guard. Sen. Tim Kaine, a Virgnia Democrat, came off the Senate floor after Flake's announcement, with tears in his eyes.
"When someone as good and decent a person as Jeff Flake does not think he can continue in the body, it's a very tragic day for the institution," Kaine told reporters.
Flake's announcement capped off a busy day on Capitol Hill. Yet another public spat between President Donald Trump and Corker, the Senate foreign relations committee chairman, dominated the morning. Trump tweeted that Corker couldn't even get elected dog catcher.
But Corker said that he and Flake hadn't coordinated their Tuesday criticisms of Trump. Instead, Corker said he had only learned of Flake's decision not to seek re-election shortly after members had lunch with Trump on Capitol Hill.
"He is kind of quiet but he stands for all the things that have made our nation great and is willing to continue to say that even though we have demagogues and others who end up trying to take us in other directions," Corker said.
Asked if Corker would consider a bid for the White House in 2020 with Flake, Corker quipped: "Oh the dog catcher theory! You know, I do like dogs."
Still, Flake's decision not to seek re-election casts questions about the future of the GOP Senate majority. Flake was only one of many GOP senators who publicly tangled with Trump over the last year. And Flake was just one of many senators who Trump ally Steve Bannon had threatened to unseat in the midterms.
If Flake was out, what did it mean for the party?
"Every senator speaks for themselves," said Sen. John Barrasso, who is up in 2018 and has been threatened with a primary challenger. "I continue to be very privileged to represent the people of Wyoming and hope to continue to do that in the future as long as they'll have me."