* Editor's note: This story has been updated throughout.
Abbott made his endorsement in a video that was released Wednesday morning.
"Conservative values are at his core," Abbott said of Cruz in the video, adding that Cruz is a "constitutionalist whose judgment I trust to appoint the right judges to the United States Supreme Court."
Abbott and Cruz appeared together Wednesday afternoon at a rally in Cruz's hometown of Houston, where Abbott hailed Cruz as his most trusted partner in his fight against the federal government.
"Lawsuits are not enough to change a broken Washington, D.C.," said Abbott, who sued the Obama administration 30-some times as attorney general. "To fix Washington, D.C., we need leaders like Ted Cruz."
Declaring that the country is at a "constitutional tipping point," Abbott also boosted Cruz on an issue the senator has been vocal about following the death of U.S. Supreme Court Justice Antonin Scalia: his replacement. Abbott, warning there is "no margin of error," declared Cruz the best candidate to appoint conservative jurists.
Speaking after Abbott, Cruz offered an extensive recollection of when he first interviewed with Abbott for the job of solicitor general of Texas. Cruz's wife Heidi was skeptical of his prospects, and Cruz admitted he "had no business at all with interviewing for the job, much less doing it."
"If you had told me in November 2002, when I was sitting in his office interviewing ... that 13 years later I'd be standing here today and Greg Abbott, the governor of Texas, would be endorsing me as president of the United States," Cruz said, quickly getting drowned out by cheers, "my reaction, quite frankly would've been like Heidi's reaction when I first interviewed for the job: 'It ain't never gonna happen.'"
Cruz now has the support of the two most powerful elected officials in Texas: Abbott and Lt. Gov. Dan Patrick, as well as former Gov. Rick Perry. Cruz has also been endorsed by roughly a quarter of the Republicans representing Texas in Congress and nearly half of the GOP members of the state Legislature.
Abbott's endorsement comes as Cruz faces serious competition on his home turf from billionaire Donald Trump, who continues to rack up wins as Cruz promises a strong showing on March 1. As results came in that showed him finishing third Tuesday night in the Nevada caucuses, Cruz said Super Tuesday would mark the "most important night of this campaign."
Abbott, the former attorney general, is a mentor of sorts to Cruz, who served as solicitor general under Abbott from 2003 to 2008. On the campaign trail, Cruz regularly recalls the nine trips he took the U.S. Supreme Court as Texas' top lawyer. He also cites the wisdom Abbott imparted as an attorney general determined to put his office on the front lines of conservative battles.
Abbott's endorsement comes after months of uncertainty about whether he would formally support any candidate in a race that started out with several participants with strong ties to Texas. Abbott had hoped to capitalize on Texas' expanded influence in the nominating process by luring White House hopefuls here to discuss issues important to the state, such as border security. Abbott met with at least two candidates: Wisconsin Gov. Scott Walker, who in March toured the border with Abbott, and retired neurosurgeon Ben Carson, who visited the Governor's Mansion in October.
It was not until the end of January that Abbott suggested he could make an endorsement, saying he could "weigh in" on the race before March 1. In recent weeks, his silence had become more noticeable to Cruz supporters eager to see the senator shore up his home-state support with the clock ticking until its nominating contest.
Abbott and Cruz are set to speak separately Wednesday night at the Harris County GOP's Lincoln-Reagan Dinner in Houston. One other presidential candidate, Carson, is also scheduled to appear at the event, which is being held on the eve on the Republican debate in Houston. The Texas primary is Tuesday.