Sen. John Cornyn (R-Tex.) kicked off his reelection campaign Friday with only token opposition standing between him and a third term.

With only about three weeks left to file for the Senate race, no marquee conservatives have stepped up to challenge the Senate's second-ranking Republican, and none are expected to, despite tea party activists' efforts to recruit a formidable candidate to run to his right.

(J. Scott Applewhite/AP)

Cornyn's strong standing can be explained by robust early preparation informed by his days as head of the National Republican Senatorial Committee, recruiting failures by opposition forces and an early primary date that offered critics little time to mobilize, compared to other states. Remarkably, it's all unfolded on potentially unfriendly terrain for Cornyn. This is the state where Sen. Ted Cruz (R) scored the biggest Senate upset of the cycle last year.

"There is nothing going on in this race," said Julie McCarty, a leading Texas tea party activist. "We had hopes of Congressman Louie Gohmert, but he declined. Then we hoped for David Barton, but he declined as well.  There are no other names being thrown around, and there is no time for a new candidate to enter the race anyway. Texas is too big to jump in this late in the game."

Barton, a Christian historian, became the latest Republican to say no when he declined to run last week. With a March 4 primary and Dec. 9 filing deadline looming, the highest-profile opponent Cornyn has drawn is attorney Linda Vega, who isn't regarded as a real threat.

Rice University political scientist Mark Jones said Cornyn has avoided drawing "even any medium-tier candidates." Most of the big GOP names, he said, have been attracted to races down the ballot.

National tea party groups have mostly avoided Cornyn's race. The anti-tax Club for Growth, known for sticking its nose into GOP primaries, isn't interested. "It's currently not on our radar," said spokesman Barney Keller. The Senate Conservatives Fund, which has already lined up behind Senate Minority Leader Mitch McConnell's primary challenger, hasn't rallied behind anyone in the Texas field, despite its distaste for Cornyn.

As chairman of the NRSC for two cycles, Cornyn witnessed firsthand the value of preparing for a primary threat early (see McCain, John and Hatch, Orrin) and the perils of a slow start (see Lugar, Richard). So he set about to hit the ground running in his own race, raising big bucks (he had nearly $7 million in his campaign account at the end of September), going up on TV early and enlisting the help of tea-party aligned strategists like Brendan Steinhauser, a former FreedomWorks hand who is managing Cornyn's campaign.

"Senator Cornyn is treating it as if it's the toughest race he's ever run. He’s home as often as he can be, traveling across the state doing things like GOP county dinners and meeting with grassroots activists," Steinhauser said.

Cornyn has hewed to a very conservative line in the Senate this year, often joining Cruz. He joined the junior Texas senator in voting against confirming John Kerry as secretary of state, for example, putting him at odds with most Senate Republicans on a matter few saw as controversial.

It's not so much Cornyn's record — he ranked as National Journal's second most conservative senator in 2012 — that irks conservative activists, said Jones, who pointed to an uneasy relationship between the senator and the grass roots as the bigger issue.

"Cornyn is viewed as an absent figure by many activists in the state, as someone who has never paid attention to the grass roots that the grass roots think they are due," Jones said.

When Cruz refused to back Cornyn this year, it was seen as a kick in his teeth, and perhaps even a signal to the conservative base to go full-bore against him. Whether it was or not is neither here nor there at this point, because a serious opponent never showed up.

Several of Cornyn's GOP colleagues are facing serious primary threats. In Kentucky, McConnell is trying to fend off businessman Matt Bevin. In Mississippi, Sen. Thad Cochran (R), who will announce whether he will make a bid for reelection later this month, would have to run against state Sen. Chris McDaniel (R), a darling of national conservative groups. And in Wyoming, Sen. Mike Enzi (R) has to contend with Liz Cheney, the daughter of former vice president Dick Cheney.

But at this point, it's pretty safe to say that Cornyn won't be mentioned in the same breath as that trio for the rest of the 2014 cycle.