Call it a conspicuous absence if you want, but Ted Cruz didn’t endorse Bill Cassidy during the primary. A Cruz endorsement would have done Cassidy a lot of good with the most conservative members of the Louisiana electorate, many of whom landed in Rob Maness’ 14 percent share of the vote, but Cassidy couldn’t get it.

Yesterday, with the runoff in Louisiana’s Senate race coming down to Cassidy and the Democrat incumbent Mary Landrieu, Cassidy got Cruz.

On Wednesday, U.S. Sen. Ted Cruz, a Texas Republican and darling of the GOP’s tea party faction, sent an email to supporters urging them to give to Cassidy’s campaign.

“He’s got a tough battle ahead of him, and needs your help,” Cruz’s email reads with an embedded donation link. “I encourage you to unite around Bill Cassidy so we can defeat Mary Landrieu.”

The endorsement isn’t all that big a deal. After all, Cruz’ endorsement of Zach Dasher couldn’t quite put him into the runoff in the 5th District race – though it almost did. But if Cruz is willing to drop into the state on Cassidy’s behalf he could definitely do the Congressman some good in unifying the Right behind the Republican.

Cassidy also got Gov. Bobby Jindal’s endorsement yesterday, but that announcement was probably more conspicuous in its timing than in its presence.

What’s more interesting than the endorsements is Cassidy’s change in tone. He’s starting to sound quite a bit more like Cruz – or, if you’d rather, like Louisiana’s other senator, David Vitter.

Challenged by Landrieu to no less than six debates in advance of the Dec. 6 runoff in an obnoxious Tuesday night speech (Landrieu said the six debates could be symbolic of the six years of a senatorial term), Cassidy didn’t quite tell Landrieu “you’ll get nothing and like it.” Instead, he agreed to one debate. It’ll be on Dec. 1, and the Raycom stations around the state will carry it.

And Cassidy matched Landrieu’s acerbic tone (which intensified in an even more obnoxious New Orleans photo-op yesterday) in his press release announcing the debate appearance…

“I will participate in a debate with Raycom Media on December 1st. Sen. Landrieu suggests six debates implying that the number six has some meaning. If we really want numbers that mean something, why not 97 debates – for the 97 percent of the time she’s supported the President’s failed agenda? Why not 716 – for the $716 billion she cut from Medicare when she chose to support Obamacare instead of our seniors. Or why not zero, the number of floor votes her clout got on the Keystone XL Pipeline and the number of times she has campaigned with President Obama.

“On that note, I issue my own challenge to Senator Landrieu: stop hiding from your record of lock-step support for President Obama. Senator Landrieu should be honest with the people of Louisiana; for every time Senator Landrieu barnstorms the state with Barack Obama, I will participate in another debate.”