Recall the timeline here: First, sick of Washington and on the outs with President Trump, Bob Corker announced his intention to retire from the Senate at the end of this term. Shortly thereafter, conservative Congresswoman Marsha Blackburn jumped into the race to fill that vacant seat, instantly rocketing into 'favorite' status. Then, amid rumors about worrisome internal polling after Democrats landed a prized recruit to try to flip the seat, Corker started floating trial balloons about reversing his decision and re-entering the contest. In response, Blackburn took a clear shot across Corker's bow, emphasizing that she's all-in, with a zero percent chance of backing away just because he's second guessing himself. As Leah reported yesterday, her comments to Hugh Hewitt were crystal clear:

“I am running, and I’m going to win,” the congresswoman told conservative radio host Hugh Hewitt on Friday. “I think what Tennesseans want to see, Hugh, is a true conservative in the U.S. Senate...“I am very drawn to doing what I can do to help preserve faith, family, freedom, hope and opportunity,” she explained. “And my husband and I decided that this is the race that would be the right race, the right fit. It was the right time for our family, so we’re in the race.” Responding to whether she believes she could defeat Corker should he decide to jump back in the race, Blackburn was confident: “I certainly do.”

It doesn't sound like she's going anywhere. And just to underscore that point, a PAC supporting her candidacy just dropped a poll showing Blackburn with a commanding lead over Corker in a hypothetical Republican primary -- and that's not all:

Poll from pro-Blackburn PAC: She leads Corker by a 2-to-1 margin in hypothetical GOP matchup & holds a five-point edge over the Dem candidate, a popular former governor: https://t.co/9amqI5CPEW — Guy Benson (@guypbenson) February 19, 2018

In a potential head-to-head matchup among Republican primary voters, the poll found 55 percent of respondents favored Blackburn, while Corker garnered just 26 percent...In a head-to-head matchup between Blackburn and Bredesen, 44 percent of likely voters said they favored the Brentwood Republican, while Bredesen netted 39 percent...In a matchup between Bredesen and Corker, likely voters supported the Democrat. Forty-four percent of voters said they favored Bredesen, compared with 35 percent for Corker.

As I noted in the tweet, these numbers should be considered with a grain of salt, given the source (Ed Morrissey points out that we don't even have access to internals or methodology); it would be nice to get some independent confirmation from a nonpartisan pollster. But if the results are even remotely accurate, Corker would face a steep uphill battle just to regain his own party's nomination, and might fare worse against the Democrats' than Blackburn would. By the way, it's interesting to see Senate Majority Leader Mitch McConnell sounding pretty bearish about the party's chances this coming fall. Here's the part of his statement that really grabbed my attention:

The top Republican in the Senate told The New York Times for a story published Saturday that "the odds are" his party will face losses in both chambers of Congress this year. “The odds are that we will lose seats in the House and the Senate,” McConnell said. “History tells you that, the fired-up nature of the political left tells you that. We go into this cleareyed that this is going to be quite a challenging election," he added. McConnell also acknowledged a fundraising deficit faced by some GOP Senate candidates in key states, a figure he attributed to those challenging incumbent Democratic senators. “I concede the fund-raising problem,” McConnell said.

This sounds like expectations management, coupled with a wake-up call for Republican donors -- but McConnell predicting losses in the House and Senate is eye-opening nonetheless. GOP losses in the lower house are nearly inevitable, but the upper chamber map is so unbelievably favorable to the majority party this cycle that projecting a net loss of seats suggests the McConnell is worried not just about the "usual" concerns (Arizona and Nevada) but others, too. Perhaps including Tennessee. And with a 51-49 majority, McConnell has almost no breathing room at all, following the Alabama debacle. Republicans should theoretically be talking about a net gain in the Senate this year, even in an unfavorable environment. Democratic incumbents appear highly vulnerable in a number of red states, and the national climate may not be as ugly as once feared. Know this: If Republicans are actually in any danger of losing the Tennessee seat, November will be a bloodbath.