After reiterating a vow that he would not campaign against Bredesen, Corker also declared that there’s “no question” the Democrat would “have crossover appeal” in November’s closely watched race to succeed him.

“I think he’s got real appeal,” the retiring Corker said of Bredesen, describing the Democrat as “a friend of mine” and a productive partner for more than two decades.

Asked about a poll earlier this month that showed Bredesen 10 percentage points ahead of Blackburn in the race, Corker told reporters at a Christian Science Monitor-sponsored breakfast that he thought that result was “probably a little heavy,” adding that Blackburn is likely down “a real six” percentage points in the race.

Even as Corker heaped praise on Bredesen, he said he would vote for Blackburn and contribute to her campaign. He also questioned whether the Democrat’s aisle-crossing persona would be enough to put him over the top.

“In a state like ours that’s still a red state, is it enough?” asked Corker, who flirted with reversing his retirement plans in February.

Blackburn campaign spokeswoman Abbi Sigler responded to the Corker comments with a jab at Bredesen, not the incumbent Republican senator.

“Phil Bredesen will be a solid vote for Chuck Schumer and Obama, Clinton-era liberal policies, and Tennesseans are not interested in that,” she said.

But Republicans working to elect Blackburn were privately frustrated by Corker’s latest bout of praise for the Democratic candidate. Bredesen sent a fundraising email Tuesday that highlighted previous positive comments from Corker.

“Senator Corker is actively trying to undermine Senate Republicans and President Trump’s agenda,” one Senate GOP campaign strategist said. “It’s sad that he is spending his last days in the Senate helping Chuck Schumer.”

Indeed, after the breakfast concluded Wednesday, Corker acknowledged that he is closer to the Democrat than Blackburn.

“The reason I speak the way I do about the [former] governor is there’s just been such an intertwined working relationship on and off for 23 years,” Corker told reporters.

“I just never have had that kind of relationship with the congressperson,” he said. “I mean, I’ve known her professionally, but it hasn’t been like we’ve been close friends and worked on issues together. I can’t think of a single piece of legislation we’ve ever worked on together.”

Burgess Everett contributed to this report.