Sen. John Cornyn (R-TX) had the whole election season to endorse Republican Senate nominee and Texas Attorney General Ken Paxton. On election night, he had no trouble putting Paxton's opponent James Talarico’s name in a tweet. Cornyn congratulated the Democrat and offered to help with his transition while the Associated Press had yet to call the race. NBC News projected that Talarico had defeated Paxton, flipping a seat Republicans had held for decades.

Earlier in the evening, the senator had posted a nighttime photo of the Texas Capitol without a caption.

Then came the message itself, telling Talarico he looked forward to meeting him and helping him get settled in the Senate.

The media called out the senator on his hasty post, as this post from CNN senior political reporter, Aaron Blake, shows:

By all means, help the new guy set up his office. But look at what each candidate got from the outgoing senator. Texas Republicans got no endorsement. Talarico got a congratulatory tweet and an offer of help.

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Back in May, President Donald Trump endorsed Paxton a week before the runoff. When Paxton won, Cornyn conceded. He’d already told Republicans they could count on him to back the ticket, whoever won. After a primary that bitter, that pledge was the right call, and there was plenty of time to make good on it. Party loyalty, it turns out, has an expiration date, and it arrived the moment he lost.

By September, the outgoing senator was headlining a Dallas fundraiser with former President George W. Bush for six Republican Senate candidates. The Republican running for his own seat wasn’t among them. CNN reported in October that he still hadn’t endorsed Paxton.

In leaked audio from a September fundraiser obtained by CNN, Paxton said Cornyn “wants me to lose,” and he cited a restaurant encounter as evidence. CNN couldn’t independently confirm that account, and Cornyn’s representative, longtime strategist Rob Jesmer, said the conversation never happened. Jesmer offered this defense: “If Sen. Cornyn wanted Ken to lose, I can assure you he’d be more active in the campaign.” That’s a funny thing to say about a man who hasn’t been active in the campaign at all.

Nor was Paxton’s complaint the only sign of the rift. By August, Cornyn was giving the Texas Tribune his assessment of the nominee. “Poor campaigner” and “lazy” were the words he chose. Lt. Gov. Dan Patrick had already warned about “sore losers undermining our party,” with the senator among those he was referring to. Republican Rep. Michael McCaul (TX-10) worried that some Republican voters might stay home altogether. That could hurt candidates farther down the ballot, too.

Paxton had to win over voters who’d spent the spring hearing why he’d make a lousy senator. His own campaign knew it and said so in an October memo. The man those voters backed could have given them a reason to show up for the Republican ticket he’d promised to support.

Republicans will spend plenty of time arguing over whether a different nominee could have held the seat. With Talarico ahead by more than a million votes in one tally, no one can say Cornyn’s endorsement alone would have saved the seat. 

It was also a rough night up the ballot, as Decision Desk HQ projected that Democrat Gina Hinojosa unseated Republican Gov. Greg Abbott, as my colleague Jennifer Oliver O'Connell wrote earlier.

Imagine being a Texas Republican who voted for Cornyn in May and took him at his word when he conceded. You watched him raise money for Republicans in other states while your own state's Senate race was up for grabs. Then, on Election Night, you finally saw him offer to lend a hand in Texas. By then, the race was already slipping away.