Democrat M.J. Hegar conceded in a sharp race to Republican incumbent U.S. Sen. John Cornyn, increasing the odds of the GOP holding on to control of the upper chamber of Congress.

The Associated Press called the race, with 69% of districts reporting: Cornyn was the projected winner with 52.6% of the votes, or 4,812,089; Hegar got 44.9%, or 4,108,413.

Hegar tweeted in defeat: “I'm so proud and incredibly grateful for all of your support. Together, we've worked so hard, and overcome so much, shattering expectations along the way. We’ve built a powerful grassroots movement from the ground up, and I know our fight here in Texas is far from over.”

Cornyn was headed to a wide margin of victory over Hegar, although early voting accelerated optimism among Democrats of a breakthrough this year after decades of defeats.

“I think our friends on the other side had so much money, they had more money than they knew what to do with, so they ended up in a long shot in places like Texas,” said Cornyn, who received a call from Hegar conceding the race less than a half hour after polls closed.

Cornyn faced his toughest reelection bid in 18 years against Hegar, whose underdog challenge in Texas got a late boost with a surge of campaign dollars and record-shattering turnout of early voters. 

Progressive congressional challengers, who back the Green New Deal, were presenting serious challenges to longtime GOP incumbents in districts that run through some of Texas’ most conservative counties.

Turnout in Texas was massive, and at record levels.

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Nearly 10 million of the state’s 16.9 million registered voters cast ballots in person or by mail during the three weeks of early voting, surpassing the number of ballots cast in the 2016 election. Election experts predicted the number of votes could surpass 12 million, which would amount to more than 70% turnout — a striking level for a state that was among the worst for turnout in 2016.

The avalanche of votes reflected high enthusiasm and signs that Texas, where Republicans have coasted in lopsided elections for decades, was rapidly transforming into a battleground.

The road to Election Day in Texas was littered with legal battles over voting access in the middle of the pandemic. Whereas the vast majority of states are allowing widespread mail-in voting because of coronavirus fears, Texas is only one of five that refused, choosing instead to expand early voting by one week.

Cornyn said in the final days of the race that he expected an outcome in the single digits, six years after he coasted to his last reelection by 27 points. His vulnerability underscored the unusual trouble Republicans up and down the ballot were 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.

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Cornyn, 68, spent the last week on a bus tour through Texas’ booming suburbs -- once rock-solid for the GOP but 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.

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

She raised about $25 million as of late October, less than other Democratic Senate challengers across the country.

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Hegar, a 44-year-old Air Force veteran, didn’t generate the same money or enthusiasm among Democrats as former U.S. Rep. Beto O’Rourke did two years ago in his nail-biting U.S. Senate run against Republican U.S. Sen. Ted Cruz.

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O’Rourke lost by less than 3 percentage points, but flipped several longtime Republican counties including Williamson, near Austin, and Tarrant, near Fort Worth.