Stockman filed for the seat minutes before the 6 p.m. local deadline. | AP Photos Stockman challenges Cornyn

Firebrand Texas Republican Rep. Steve Stockman on Monday mounted a surprise primary challenge to Sen. John Cornyn (R-Texas), setting the stage for the latest potentially explosive battle between a tea party darling and an incumbent firmly backed by the GOP establishment.

Stockman, a far-right conservative who has called for the president’s impeachment, filed for the seat minutes before the 6 p.m. local deadline, confirmed Spencer Yeldell, a spokesman for the Republican Party of Texas. Cornyn, whose $7 million cash-on-hand far outstrips Stockman’s $32,000, is still the heavy favorite, but the latter’s entry into the race could force the incumbent senator to tack farther right as he tries to win over a corner of the party that has recently been skeptical of him.


Stockman’s move shocked Texas political observers: Cornyn had looked poised for an easy March 4 primary contest, where he was set to square off with several candidates with little name recognition. Just 20 minutes before the filing deadline, Texas GOP chair Steve Munisteri told POLITICO that he was “not expecting any recognizable names or people with substantial resources running aside from the senator.”

( PHOTOS: Senators up for election in 2014)

But Stockman is a highly recognizable name in some circles, and he looks to be a game-changer. The 57-year-old made waves earlier this year when he returned to the House — where he previously served from 1995-1997 — with his calls to impeach President Barack Obama. And he’s not been shy about his other deeply conservative, and sometimes controversial, views on issues ranging from gun rights to immigration. He has also likened Obama to Saddam Hussein and urged America to withdraw from the United Nations.

The Stockman-Cornyn match-up will be the latest in a series of contests that pits tea party-backed candidates against incumbents deemed insufficiently conservative by GOP purists. In Kentucky, for example, tea partiers have rallied around Matt Bevin, who is taking on Senate Minority Leader Mitch McConnell. And in Mississippi, some conservatives are waging battle against incumbent GOP Sen. Thad Cochran.

Tea party types have been angling for a fight with Cornyn, 61, since this fall, when he didn’t back Lone Star State colleague Sen. Ted Cruz (R) in a procedural motion designed to derail funding for Obamacare ahead of the government shutdown. That move led the Senate Conservatives Fund to blast Cornyn as a “turncoat” and enraged conservatives back home.

( Also on POLITICO: Senate passes legislation on undetectable guns)

But ultimately several tea party favorites — including Rep. Louie Gohmert (R-Texas) and historian David Barton — decided not to take on Cornyn, leaving the field of challengers to lesser-known figures until Stockman’s last-minute entry. The Senate Conservatives Fund on Monday stopped short of endorsing Stockman, but heralded his foray into the race.

“We haven’t decided yet whether we will endorse Steve Stockman, but we’re glad he is running,” Matt Hoskins, the group’s leader, said in a statement. “Texas deserves two conservative fighters in the Senate, not just one. John Cornyn has voted to increase the debt, raise taxes, bail out Wall Street banks, and fund Obamacare. He’s part of the problem in Washington and voters deserve an alternative.”

Cornyn aides stressed his conservative bona fides late Monday.

“Endorsed by Texas Right to Life and ranked as the second most conservative senator in America, Senator Cornyn looks forward to discussing his conservative record with Texans,” Cornyn campaign manager Brendan Steinhauser said in a statement following news of Stockman’s challenge.

( Also on POLITICO: Why the timing is right for a budget deal)

Despite the outrage over his disagreement with Cruz, Cornyn is considered quite conservative, even by Texas standards. He also was able to fend off a serious primary challenge for so long in part because his name recognition and deep war chest make him a formidable candidate in the vast and astronomically expensive state.

While Stockman had just $32,000 cash-on-hand as of the last filing, his campaign also is more than $163,000 in debt. He will have a daunting task trying to raise funds and catch up to Cornyn’s name recognition with less than three months until the primary. Cornyn, the former chairman of the National Republican Senatorial Committee, will also enjoy a wide network of establishment support.

“John Cornyn is one of the most conservative members in the Senate and strong leader for the state of Texas,” said NRSC spokesman Brad Dayspring. “We are proud to support Senator Cornyn and while this primary challenge is quite the head scratcher, it will be defeated.”

Cornyn also has been working on outreach to the tea party — his campaign manager is a veteran of FreedomWorks — and his team kicked off an ad campaign this fall.