Tea Party favorite State Rep. Joe Carr of Tennessee has decided to challenge GOP Senator Lamar Alexander in the primary next year, calling him "the most liberal member of the delegation from Tennessee."

Carr was mulling a run against Rep. Scott DesJarlais, who is reeling from recent revelations of infidelity and urging his wife to get an abortion after she got pregnant as the result of an extramarital affair.

Washnington Post:

Meanwhile, Alexander is one of Tennessee's most seasoned politicians. He is a former two-term governor who twice ran for president, served as U.S. secretary of education and as president of the University of Tennessee. He also had $3.1 million in the bank for his re-election effort through the first half of the year.

Carr said he expects it will take more than $5 million to defeat Alexander, including independent expenditures. He had about $275,000 on hand from his House race through the middle of the year.

"Lamar is popular, but there is a disconnect with his popularity to the way he has voted," Carr said.

An Alexander spokesman did not immediately comment on Carr's announcement, but in an opinion piece in The Tennessean newspaper Tuesday, Alexander defended his conservative credentials.

"I believe that one good way to put our country on the right track is to send to Washington a conservative, problem-solving former governor who worked well with others to get the results that put our state on the right track," Alexander said.

It's unclear whether Carr's entry will ward off other challengers to Alexander, who has already spent close to $1 million on his campaign, including on TV ads featuring Sen. Rand Paul, a tea party favorite, saying: "Nobody wants to say no to Lamar Alexander."

Carr was elected in 2008 to an open seat in the state House, where has sponsored legislation seeking to address illegal immigration, gun rights and reduce state sales taxes on coins and bullion. Earlier this year, he proposed making it a crime in Tennessee for federal agents to enforce any effort to ban firearms or ammunition in response to last year's shooting at a Newtown, Conn., elementary school that left 20 students and six teachers dead.

"We're tired of political antics, cheap props of using children as bait to gin up emotional attachment for an issue that quite honestly doesn't solve the problem," Carr said at the time.

The bill, which ultimately failed in a Senate committee, would have also required the state's attorney general to defend any Tennessean prosecuted for violating the potential federal gun violations.

And so the bloodletting continues. I doubt whether Carr can defeat Alexander, despite Tea Party support. Alexander is very popular, has low negatives, and the Democrats aren't running anyone of note against him. To beat him, Carr would have to savage him to bring his negatives up and raise a lot more than the $5 million he thinks he needs.

He probably won't win but he can do a lot of damage to the Senator in a brutal primary. A lot of energy and resources expended for no good reason.