Defying all early expectations and upending long-standing conventional wisdom in Texas Republican politics, former Texas Solicitor General Ted Cruz handily won the Republican runoff for an open U.S. Senate seat Tuesday night.

He moves on to the general election against former state Rep. Paul Sadler, who defeated retired educator Grady Yarbrough in the Democratic runoff.

Cruz defeated Lt. Gov. David Dewhurst after a lengthy, contentious political battle in which Cruz painted a longtime statewide elected official backed by Gov. Rick Perry as a moderate.

“Tonight is a victory for the grass roots,” Cruz said Tuesday night. “It is a testament to Republican women, to Tea Party leaders and to grass-roots conservatives.”

In a short concession speech, Dewhurst said he was proud of the race he had run.

“We got beat up a little bit, but we never gave up,” Dewhurst said. “And we stand tall in knowing that we never compromised any of our values.”

In a statement, Sadler made clear that he will fight for Dewhurst’s supporters ahead of the Nov. 6 general election.

“Tonight, I stand alone as the only nominee of a major political party in Texas because the Texas Republican Party has been hijacked by the Tea Party,” Sadler said in a statement.

The fight for the GOP nomination to replace U.S. Sen. Kay Bailey Hutchison drew strong national interest and more than $45 million in spending, making it the nation’s most expensive nonpresidential race of the election cycle, according to the Center for Responsive Politics.

From the start, the race appeared to be Dewhurst’s to lose, as he had held statewide office for more than a decade and had millions of dollars in personal wealth at his disposal to outspend any opponents. But many influential activists aligned with the Tea Party were unimpressed with Dewhurst’s record and could not shake the feeling that he would crumble to pressure from moderates once in Congress.

Cruz also benefited from protracted legal fighting over last year’s congressional and legislative redistricting maps that pushed the Texas primary from March to May and the subsequent runoff to July. The longer primary gave Cruz more time to introduce himself to the state’s Republican voters. 

Though Dewhurst and Cruz agreed on practically every major issue, the race still managed to draw passions on both sides as the race turned largely on the candidates’ temperaments and records. 

Cruz, a Cuban-American, Harvard-educated lawyer who worked on George W. Bush’s 2000 presidential campaign and later for the Bush administration, centered his Senate campaign on his five-plus years as Texas Solicitor General under Attorney General Greg Abbott. In fiery speeches, he cited his work on cases dealing with states’ rights, gun control and religious freedom as a “proven record” of “fighting for the U.S. Constitution.” Conservative stars including former Alaska Gov. Sarah Palin and U.S. Sen. Jim DeMint, R-S.C., endorsed Cruz’s campaign.

Dewhurst, who has served as lieutenant governor since 2003, pointed to a long list of conservative legislation passed under his watch, as well as his experience as a businessman and service in the Air Force and CIA.

Cruz relentlessly criticized Dewhurst as “timid” and a “moderate,” accusing him of raising state spending and blaming him for conservative measures not becoming law.

Texas Republican leaders including Perry and more than half of the Texas Senate endorsed Dewhurst and accused Cruz of distorting Dewhurst’s legislative record and, simultaneously, their own records as well. 

Dewhurst attacked Cruz for some of the clients he has taken on as a private lawyer and painting him as a “Wasington insider.” He described millions spent by the Club for Growth and other anti-tax groups to boost Cruz’s campaign as out-of-state meddling from people who didn’t care about Texas. None of the attacks seemed to blunt momentum for Cruz.

On the Democratic side, Sadler adopted some of Dewhurst’s criticism of Cruz on Tuesday night, describing the Republican nominee as  “untested, untried and unknown to the vast majority of Texans.”

Yarbrough, who has never held elected office, said he would support Sadler in November. The perennial candidate surprised many by making it into the Democratic runoff. Though he invested much of his personal savings into his campaign, he said he didn’t regret entering the race. 

“I enjoyed it quite a bit, tremendously,” Yarbrough said. “You never know how elections are going to go. Sometimes they go the way you think they’re going to go and sometimes they don’t.”

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