The United Auto Workers achieved a landmark victory last fall, when a strike against the Big 3 U.S. carmakers delivered substantial gains for nearly 150,000 employees.
The UAW stands poised for its next major test this week: A union election at a foreign-owned car plant in the South, where its workers have struggled to gain a foothold for decades.
Roughly 4,000 voters at a Volkswagen facility in Chattanooga, Tennessee, begin casting their union ballots today.
Experts who spoke to ABC News called the election an inflection point not only for the UAW but for the U.S. labor movement.
In the aftermath of the so-called “Year of Strikes” in 2023, experts said, the showdown in Chattanooga could illustrate whether that surge of labor activity can translate into membership growth and the worker gains likely to come with it.
"The stakes couldn’t be bigger," Stephen Silvia, a professor at American University and the author of "The UAW's Southern Gamble," told ABC News.
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The high-profile standoff between UAW and the Big 3 last year imposed billions of dollars in losses for the companies and put thousands of workers temporarily out of work. But the gamble paid off, helping the union achieve historic wage gains and other long-sought reforms.
The agreement prompted some non-union competitors to offer pay increases and other benefits, putting their employees in closer alignment with UAW members. Honda, Nissan and Tesla are among the car companies that raised wages for U.S. employees after the UAW deal.
The breakthrough also triggered a wave of UAW organizing, the union says. Over 10,000 non-union autoworkers have signed cards in support of the UAW in recent months and organizing campaigns have broken out at more than two dozen facilities, the union said in a statement last month.
The outcome of this week’s union election at Volkswagen will go a long way in determining whether the union’s momentum continues to crest or fizzles out, experts told ABC News.
In response to ABC News' request for comment, Volkswagen said it supports the union election process.
"We respect our workers' right to a democratic process and to determine who should represent their interests," the company said. "We fully support an NLRB vote so every team member has a chance to a secret ballot vote on this important decision. Volkswagen is proud of our working environment in Chattanooga that provides some of the best paying jobs in the area."
UAW did not immediately respond to ABC News' request for comment.
A wave of union victories would bolster the UAW’s membership, which has dropped steadily from a peak of 1.5 million workers in 1970 to 370,000 last year.
"This is huge for the UAW because they’re carrying so much momentum," Art Wheaton, director of labor studies at the Worker Institute at Cornell University, told ABC News. "The timing is now."
The location of the Volkswagen plant in the union-unfriendly South holds significance for the prospects of a resurgent labor movement aiming to make inroads there, experts told ABC News.
For decades, states across the South have imposed so-called "right-to-work" laws, which give workers the opportunity to opt out of union membership in the event that their workplace votes to join a union.
Those measures make up part of a larger set of legal and cultural barriers that make union organizing more difficult in the South, experts said.
"Organizing is extremely difficult in the South not only because of management opposition but also workers don’t have as much experience with unions," Harry Katz, a professor of collective bargaining at Cornell University, told ABC News.
The UAW campaign exemplifies the significance of organizing in the South. Roughly 48% of U.S. autoworkers belong to the unionized Big 3 automakers –--Ford, General Motors and Stellantis, the owner of Chrysler, Wheaton said. Meanwhile, more than half of autoworkers are employed at foreign-owned, largely non-union car companies, many of which are located in the South.
The non-union companies put downward pressure on wages and benefits, making it more difficult for the UAW to bargain for gains at plants where it represents workers and in turn help preserve decent standards across the industry, he added.
"They need to have more people unionized so they have a larger impact on raising the wages for everyone," Wheaton added.
More than 500,000 workers went out on strike nationwide in 2023, more than doubling the figure recorded a year earlier, according to Cornell University's School of Industrial and Labor Relations.
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The surge of activity, however, failed to translate into union membership growth. Only 10% of U.S. workers belonged to unions last year, little changed from the year prior, U.S. Bureau of Labor Statistics data showed.
The union vote at Volkswagen, which arrives months after the UAW strike against the Big 3, could show whether militant activity brings union growth, Silvia said.
"This is a test case for whether making gains at the bargaining table can then add to your membership down the road,” he added.