Gov. Greg Abbott stayed out of the September special election for a Texas state Senate seat in rural North Texas, content to let his coronavirus response become a flashpoint between two members of his own party.

But now that the race is down to a Saturday runoff, Abbott has gone all in.

The race pits state Rep. Drew Springer of Muenster against fellow Republican Shelley Luther, the Dallas salon owner who went to jail after defying Abbott’s pandemic orders earlier this year. Ahead of the 2021 legislative session — and the 2022 primary season — Abbott is determined to make an example out of Luther, who has become an avatar of his intraparty detractors.

Abbott endorsed Springer earlier this month, making official a preference that many had suspected after Luther spent months lacerating Abbott’s pandemic management. The governor’s campaign has since made over a quarter-million dollars worth of in-kind contributions to Springer. And in the runoff’s final week, his campaign is airing a TV spot attacking Luther, the first time it has spent serious ad dollars against a member of his own party since he sought to defeat a trio of state House Republicans in the 2018 primary.

“What are they so afraid of?” Luther asked during a debate Wednesday, leaning in to the proxy war that was apparent before the September election but has become far more explicit since then.

As Abbott has poured his campaign resources into the runoff, Luther has received even more funding from Tim Dunn, the hard-right megadonor and board chair of the advocacy group Empower Texans who has overwhelmingly bankrolled her campaign. After loaning Luther $1 million during the first round, he has donated $700,000 to her in the runoff, including $200,000 on Monday.

Springer said during the debate that Luther has taken “$1.7 million from a billionaire in West Texas who is trying to buy this seat.”

“He knows he will control Shelley Luther,” Springer said, “and that is why he is willing to spend that kind of money.”

Luther and Springer are running to replace Sen. Pat Fallon, R-Prosper, as he prepares to join the U.S. House in January. The Senate district is solidly red and covers a large patch of North Texas, largely rural, that wraps around the Dallas-Fort Worth area.

The two finished close together in the six-way September special election, with Luther edging Springer by 115 votes.

While at least a couple of new issues have cropped up in the runoff, the race remains animated by Abbott’s coronavirus handling and conservative angst over it. There was a fresh reminder of the state’s restrictions earlier this month when a large part of North Texas had to roll back business reopenings because its hospital region saw coronavirus patients make up more than 15% of its capacity for seven straight days.

When Abbott endorsed Springer, Luther issued a response that reminded supporters that it was the governor’s “unconstitutional orders that put me in jail for opening my business.” (Abbott later updated an order to remove the threat of jail time.) And at the end of the response, Luther attached an illustration depicting the runoff as a choice between Abbott and Springer, both wearing masks, and her and President Donald Trump, both unmasked.

To be sure, Springer has been working to burnish his anti-lockdown credentials in the runoff. He pre-filed bills for the next legislative session to curb the governor’s emergency powers, and even after Abbott endorsed him, he pleaded with the governor on Facebook to “please open Texas and get our state back to work!”

Luther has said Springer is scrambling to match her anti-lockdown zeal — and has not let up on her own Abbott antagonism, calling for him to face a 2022 primary challenge during a GOP rally earlier this month in Dallas.

Cooke County Judge Jason Brinkley, who has endorsed Springer, acknowledged there is “a lot of restriction fatigue” in the area but said he was backing Springer due to his experience and “ability to hit the ground running” for what is expected to be a tough legislative session.

“I think there’s legitimately some people that are so frustrated with everything going on that they want drastic change and are willing to overlook other qualities and qualifications that they normally would” prioritize in a candidate, Brinkley said. “But I think the majority of people understand that even if you may not agree with everything going on — and even as a county judge I don’t agree with everything the governor’s done — there is understanding that there was some purpose and some reasoning behind it.”

Asked if that latter group favors Springer, Brinkley said, “I would like to think so, yes.”

The specter of Abbott has been overwhelming in the runoff’s closing days. In addition to the governor’s endorsement, in-kind contributions and TV buy, his top political strategist, Dave Carney, started this week sparring with Luther and her allies on Twitter.

Dunn’s involvement in the runoff has also taken nonfinancial form. Last month, he made a somewhat rare public appearance to campaign for Luther, speaking at a meeting of the Parker County Conservatives that she also attended.

Mike Olcott, co-founder of the Parker County Conservatives, which supports Luther, said he has seen a “split reaction” to Abbott’s endorsement, with it helping Springer among some voters and boosting Luther among others.

Lt. Gov. Dan Patrick, the president of the Senate, has not followed Abbott's lead in the runoff, remaining neutral and only wading in to prod Springer and Luther to support a key rule change proposal for the upcoming session. (Both quickly obliged.) And while Texas GOP Chair Allen West has also been a leading intraparty critic of Abbott’s coronavirus response, he has taken pains to stay out, recently threatening to send a cease-and-desist letter to Luther’s campaign over alleged misrepresentations of his position in the runoff.

As the runoff winds down, both Springer’s campaign and Abbott’s are airing TV ads that pounce on a June tweet in which Luther expressed solidarity with the Black Lives Matter movement when it comes to keeping business open during the pandemic. Springer’s ad claims Luther “praised dangerous radicals and rioters.” In a sign that it may be a potent line of attack, Luther released an ad Wednesday denouncing Black Lives Matter as a “Marxist organization” and decrying Springer’s “false attacks.”

While Luther’s Black Lives Matter tweet came up in the first round, there have been at least a couple of newer barbs in the runoff. Springer has run radio and TV spots claiming Luther resigned from teaching jobs “under mysterious circumstances” — circumstances neither side appears particularly eager to explain. And Luther’s campaign has put her dad in one TV commercial to assail Springer, citing an earlier incident in which Springer’s father apparently wrote on a flyer about the race, asking, “Who is [Luther] sleeping with this month?” (Springer’s dad later apologized.)

If that were not dramatic enough, Luther has sought to draw attention to an unsuccessful Springer bill that would have regulated drones — by filming herself shooting one out of the air in a backyard.

Both campaigns are confident ahead of Saturday but cognizant of the uncertainty over who will turn out for a special election runoff that is happening in the shadow of the draining November election and six days before Christmas. As it tries to figure out a winning coalition, Springer’s campaign has apparently been appealing to Democrats, sending out a mailer that attacks Luther from the left on how she has dealt with the pandemic — saying she “ignores science,” for example — and touting that Springer is committed to proposals like protecting health insurance coverage for people with preexisting conditions.

(The race is not a primary battle, but features two Republicans because they were the top two recipients of votes in the first round of voting. That round included one Democratic candidate, who finished third with 21% of the vote.)

The runoff, though, has been dominated by the intra-GOP divide. Olcott said Saturday will offer a “barometer on that divide.”

“There is a very clear line — either you support the grassroots conservatives by supporting Shelley Luther or you support the Austin establishment by supporting Drew Springer,” Olcott said, “and this race epitomizes that.”