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MCKINNEY, Texas – The crowded and combustible GOP primary race for Texas attorney general is headed for a May runoff. 

The two-term Attorney General Ken Paxton, who's known nationally for trying to legally upend the 2020 presidential election results and who enjoys the backing of former President Donald Trump, failed to top 50% of the vote in Tuesday's primary, forcing him into a May runoff.

He will face two-term Texas Land Commissioner George P. Bush.

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"May 24 is not that far away. We haven’t won anything. Tomorrow we start zero-zero," Paxton told supporters on Tuesday night in his hometown of McKinney, as he acknowledged he was headed for a runoff.

Ken Paxton primary night in Texas

Republican Attorney General Ken Paxton of Texas speaks to supporters on primary night, in McKinney, Texas on March 1, 2022 (Fox News)

Bush narrowly edged former state Supreme Court justice Eva Guzman, according to unofficial primary results as of Wednesday morning, with Rep. Louie Gohmert in fourth place.

With 86% of polling locations reporting, Paxton led with 42.85% Bush was next with 22.6%. Guzman and Gohmert each had 17%.

"Looking like things are going in our direction," Bush told reporters at his primary night watch party in Austin. "Texans have spoken pretty clearly that they want something different."

Paxton, who's taken President Biden's administration to court numerous times over the past year, has showcased his conservative record as he seeks the GOP nomination. 

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But he's been repeatedly attacked by Bush, Guzman and Gohmert over the slew of corruption allegations that he faces.

The conservative attorney general told his supporters that the "establishment, they got what they wanted, they got me in a runoff."

And looking ahead to the runoff campaign, Paxton predicted that "a lot of money is going to go to the other side….There are people who want to control this office."

Paxton grabbed national attention for filing the unsuccessful Texas vs. Pennsylvania case in the Supreme Court that tried to overturn now President Biden’s razor-thin win over Trump in the Keystone State, and for speaking at the then-president’s rally near the White House that immediately preceded the deadly Jan. 6 attack on the U.S. Capitol by right wing extremists aiming to disrupt congressional certification of Biden’s Electoral College victory.

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But Paxton’s challengers targeted him less on his record and agenda and more on his political baggage.

George P. Bush

Texas Land Commissioner and GOP attorney general candidate George P. Bush joins volunteers in phone banking on the eve of the Texas primary, on Feb. 28, 2022 (Fox News)

Paxton was indicted on securities fraud charges soon after taking office in 2015, and more recently came under investigation by the FBI over bribery and corruption allegations from former top staffers. Paxton has denied any wrongdoing in either case.

Asked about the ongoing federal investigation, Paxton told Fox News on Monday that "I don’t know what they’re going to do. All I can tell you is that we were doing the right thing. We’re going to continue to do the right thing."

But Bush, the last member of the Bush political dynasty – which over four generations has produced two presidents, a vice president, a senator, two governors and a congressman – has continuously spotlighted Paxton’s ethical issues since launching his challenge last June.

"We can’t take that risk," Bush told Fox News on the eve of the primary. "As Republicans we’ve got to go with someone who’s above reproach and not facing criminal suspicion."

Former Texas Supreme Court justice Eva Guzman, who's running for state attorney general, greets voters at the Texas Federation of Republican Women convention in San Marcos, Texas in January, 2022  (Guzman attorney general campaign)

Paxton had the backing of former President Donald Trump, who remains very popular and influential with Republican voters in Texas and across the country. The former president, in a recent campaign ad, called Paxton an "attorney general who has really led the way. Somebody who has been brave and strong."

Bush, who made a full court press for the former president’s endorsement, told Fox News "I think he [Trump] made a mistake, which is fine because Ken wasn’t exactly forthright with the people of Texas, let alone the president about his own legal issues."

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The race has turned increasing nasty in recent weeks.

Paxton's campaign last week went up with an ad taking aim at Guzman.

Guzman, pushing back against at attack from the attorney general’s team, charged that "Ken Paxton has a history of lying." And she told Fox News that "I’m not surprised he’s lied to the people of Texas about me. It reeks of desperation."