Republican Sen. John Cornyn faced his toughest reelection bid in 18 years on Tuesday against Democrat MJ Hegar, whose underdog challenge in Texas got a late boost with a surge of campaign dollars and record-shattering turnout of nearly 10 million early voters.

Cornyn said in the final days of the race that he expected a narrow outcome in the single digits, six years after the GOP's former second-in-command in the Senate coasted to his last reelection by 27 points. His vulnerability underscored the unusual trouble Republicans up and down the ballot are suddenly confronting in America's biggest red state.

Hegar was trying to become the first Democrat in more than 30 years to win a U.S. Senate race in Texas.

“You can feel it, that we're winning these races up and down the ballot in Texas and that means we have an opportunity. Because the fight never ends, y'all," Hegar said Monday in San Antonio.

Cornyn, 68, spent the last week on a bus tour that included Texas’ booming suburbs that were once rock-solid for the GOP but have begun rapidly tilting toward Democrats.

“It's a full frontal attack,” Cornyn said of the money Democrats have poured into races during a weekend stop in Abilene. "We need to meet it with a similar response. We need to stop these people before they change Texas forever."

Hegar, a 44-year-old Air Force veteran didn't generate the same money or enthusiasm among Democrats as former congressman Beto O'Rourke did two years ago in his nail-biting U.S. Senate run against Republican Ted Cruz. She had raised about $25 million as of late October, less than other Democratic Senate challengers across the country.

But dramatic turnout — some elections experts predicted Texas could wind up with more than 12 million votes — fueled expectations of a close finish. Hegar spent the final days of the campaign crisscrossing the state, including with vice presidential contender Kamala Harris, who showed up in Texas closer to Election Day than anyone on a Democratic presidential ticket has in years.

Cornyn, 68, spent the last week on a bus tour through Texas' booming suburbs that were once rock-solid for the GOP but have begun rapidly tilting toward Democrats. He attacked Hegar as too liberal and also sought to damage her support among Black voters by highlighting how one of her primary challengers, state Sen. Royce West, said he wouldn’t vote for her.

Hegar ran as a middle-of-the-road fighter, and although she criticized President Donald Trump, she didn’t go out of her way to do so while keeping her attacks on Cornyn.

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