The vote by workers at a Chattanooga VW plant to join the union tested its renewed organizing effort in the South amid GOP opposition.

For decades the labor movement has seen its power diminish in the South. The United Auto Workers on Friday jump-started efforts to reverse that decline.

The UAW delivered one of the labor movement’s biggest organizing victories in the South in years when Volkswagen workers in Tennessee voted overwhelmingly to join the union, despite efforts by the state’s Republicans to doom the effort.

The UAW has eyed the Chattanooga facility for over a decade, and the union narrowly lost a pair of previous elections in 2014 and 2019, the latter of which was decided by about 60 votes. This time, workers voted 2,628 to 985 to join the UAW out of more than 4,000 who were eligible, marking a key victory for union President Shawn Fain’s ambitious strategy to take on non-union automakers in the U.S.

“Many of the talking heads and the pundits have said to me, repeatedly, when we announced this campaign, ‘You can’t win in the South.’ They said Southern workers aren’t ready for it,” Fain told workers late Friday. “You all moved a mountain.”

The UAW’s blueprint drew heavily on momentum gathered as a result of last year’s high-stakes strike at the Big Three car companies, which drew President Joe Biden to its picket line and dominated headlines for months. It also bolstered relationships developed with VW workers in the years since supporters first started organizing in Chattanooga.

“This time the atmosphere has changed,” Renee Berry, a VW worker since 2010, told POLITICO. “There’s been so many people that voted against it in 2014, 2019, but now they’re on board.”

The Germany-based car manufacturer throughout each of the organizing drives has officially remained neutral, though the UAW in 2019 contended that VW repeatedly violated that principle and those tensions lingered into this week’s vote. The UAW has filed unfair labor practice charges against VW, accusing it of illegal anti-union tactics, which the company denies.

Following Friday night’s vote, VW thanked the workers for participating in the election.

Compared to other non-union competitors like Tesla, whose leader Elon Musk unabashedly opposes unionization and has repeatedly battled with the National Labor Relations Board, VW’s position placed self-imposed limits on how it could address UAW’s messaging.

That left Tennessee’s top elected Republicans to lead the fight against the union. They argued that the UAW’s presence could deter future investments or encourage VW and other employers to consider bringing jobs to other states instead.

In 2014, then-Sen. Bob Corker, who’d previously been Chattanooga’s mayor, was among those who aggressively worked to turn workers against organizing with the UAW.

“This is all about money for them. They feel like, if they can get up under the hood with a company in the south, then, they can make progress in other places,” Corker told the Washington Post in 2014.

A representative for Corker declined an interview request with the former senator, who retired at the end of his term in 2018.

Similar messages at the time came from Gov. Bill Haslam and other powerful figures like state Sen. Bo Watson, who called VW’s posture “un-American” and floated the prospect of cutting off financial incentives to the company. (Watson’s office did not respond to an email from POLITICO.)

Ultimately, workers in 2014 voted 712-626 against the union, which fumed at the opposition from “politicians and outside special interest groups.”

The GOP used a similar playbook five years later, with Haslam’s successor as governor — Bill Lee, who owned a construction contracting business — touring Volkswagen’s plant and extolling the benefits of a non-union shop to workers in Chattanooga.

However, such foreboding rhetoric didn’t land hard enough this time to discourage workers from vindicating the UAW’s decadelong quest.

Earlier this month Lee said unionization would be “a big mistake,” and he recently joined a suite of fellow Southern governors in projecting a unified front against the UAW — and tried to sway GOP-leaning workers by yoking the union to Biden, whom the UAW endorsed in January after a protracted delay.

“They proudly call themselves democratic socialists and seem more focused on helping President Biden get reelected than on the autoworker jobs being cut at plants they already represent,” the letter stated. “We want to keep good paying jobs and continue to grow the American auto manufacturing sector here. A successful unionization drive will stop this growth in its tracks, to the detriment of American workers.”

The broadside was led by Alabama Gov. Kay Ivey, whose state is set to be the next battleground as the UAW is scheduled to hold an election of Mercedes-Benz workers there next month. Back-to-back victories could turbocharge further auto-industry organizing and dent the South’s reputation as hostile terrain for labor unions.

Biden lauded the VW results and directly rebuked the GOP pressure.

“Let me be clear to the Republican governors that tried to undermine this vote: there is nothing to fear from American workers using their voice and their legal right to form a union if they so choose,” he said in a statement released by the White House. “I will continue to stand with American workers and stand against Republican’s effort to weaken workers’ voice.”