If you want to know where Nina Turner is coming from, take a look at where she has been.

I got to know the Ohio congressional candidate more than a decade ago, long before she was cochairing campaigns for Bernie Sanders and leading national progressive organizations. Back then, she was an Ohio state senator who was defending labor rights against one of the modern era’s fiercest assaults on unions and their members.

The 2010 midterm elections had swept Republican governors and legislators into power in the Great Lakes states. Where Republicans had once competed for labor support in these states—sometimes with considerable success—these new governors and legislators were determined to use their positions to undermine the power of unions in general and public-sector unions in particular. Like their assaults on voting rights and their gerrymandering schemes, this was a political gambit. The focus on rewriting the rules with regard to organizing and collective bargaining was designed to appeal to the anti-union passions of billionaire donors like the Koch brothers, and to strengthen the position of Republicans in the battleground states where contests for the presidency and control of the Congress would be decided.

The leader of the charge was Wisconsin Governor Scott Walker, whose first major initiative in 2011 was a move to strip away the collective-bargaining rights of public-sector unions. Despite the fact that Walker’s move provoked mass protests, other Republicans followed his lead. One of the most ardent of their number was Ohio Governor John Kasich, who like Walker wanted to position himself as a 2012 or 2016 GOP presidential prospect.

Turner pushed back against Ohio’s anti-labor legislation—known as Senate Bill 5—in a big way, as I did with regard to Walker’s program in Wisconsin. We often found ourselves sharing time on cable TV programs, especially Ed Schultz’s old MSNBC show. When we spoke recently about those days, Turner recalled that in the state Senate, “I helped lead the fight against Senate Bill 5. The legislation passed. But, thank God, in Ohio, we had the power of referendum. The people get to have the last say, to reject something that the legislature puts forward, and that was a campaign that took on national implications, as we know.”

Unlike in Wisconsin, where Walker and his anti-labor associates prevailed, Ohio’s Constitution permitted the people to veto noxious legislation. The campaign to overturn Senate Bill 5 was an epic struggle—led by the Ohio unions and allies such as Turner. Petitions with 1.3 million signatures—915,000 of which were eventually certified—forced a November referendum on whether the new law should be implemented. The campaign was intense. “We got out there and fought against that law,” recalled Turner, “and we convinced the voters of the state that the Republican-controlled legislature went too far.”

Indeed, they did. The referendum result was a 67-33 blowout. More than 2.145 million voters backed the move to overturn Senate Bill 5, while just 1.352 million voted to retain it—in one of the biggest wins for organized labor in recent decades.

Turner’s experience in the fight to overturn Senate Bill 5 won her a lot of working-class allies. In Tuesday’s special election to fill an open House seat representing Ohio’s 11th district, the Democratic primary features 13 candidates. Union endorsements have been spread around, as is common in a crowded Democratic contest. But Turner’s got a notable list 0f labor backers, including activist unions such as the National Nurses United, the Amalgamated Transit Union, the American Postal Workers Union, SEIU District 1199, the Retail Wholesale and Department Store Union (which recently took on Amazon), and key regional units from the Communication Workers of America, the International Association of Machinists, and the Bakery, Confectionery, Tobacco Workers and Grain Millers’ International Union.

The Ohio contest has shaped up as a fight between progressives and centrists. Turner is supported by Sanders (who will campaign for her this weekend) and leading progressives such as Congressional Progressive Caucus chair Pramila Jayapal (D-Wash.), US Representative Alexandria Ocasio-Cortez (D-N.Y.), US Representative Jamaal Bowman (D-N.Y.), and US Representative Ro Khanna (D-Calif.), as well as Cleveland Mayor Frank Jackson and former Dayton mayor Rhine McLin. Her chief rival, Cuyahoga County Council member Shontel Brown, is backed by former secretary of state Hillary Clinton, House majority whip James Clyburn (D-S.C.), and some unions—but also some Republican-leaning donors who have in the past aided corporate-friendly Republicans.

Most Democrats who go to Congress are generally supportive of labor. But if Turner wins, she says she plans to serve as a fierce advocate for workers and the organizations that represent them—promising as a central premise of her economic and social and racial justice agenda to “strengthen and expand unions.”

“I’ve definitely been in the trenches with my labor sisters and brothers over the decades. I’m excited and proud to enjoy the support of many labor unions,” she told me when we spoke recently. “So yes, I’ll be with the unions, whether its on the floor of the House or marching in the streets. I’ve already been in the streets with labor unions as they have been pushing, not just in my state but all across the country—from postal workers to the Fight for 15 that’s being led by SEIU. I’ve been there side-by-side with these workers, and it is a source of pride for me.”

Right now, Turner is enthusiastic about the Protecting the Right to Organize Act, which would make it easier for unions to organize and collectively bargain. “I’m really glad that it passed the House of Representatives,” she says of the PRO Act. “We’ve got to get it through that other chamber, the Senate, which is going to be a herculean task. It shouldn’t be, but it is going to be.” She’s also focused on trade policy, an issue that has often divided Democrats.

On what has long been a “Which side are you on?” issue, Turner’s on the side of the unions that have battled against bad trade deals—such as the North American Free Trade Agreement and permanent normalization of trade with China—that have been backed by presidents and members of Congress from both parties.

“Steel was king or queen in the greater Cleveland area, that industry, and in other parts of the district that I’m running in. For Akron it was rubber. So I come from a state and a district where labor unions and good-paying jobs were a staple. That was how many people made it into the middle class,” she says. “Ohio certainly has been devastated, my district especially, by the loss of good-paying manufacturing jobs because of bad trade policy. You know the notion of the bad trade policies was centered in the 2016 presidential election especially. We have got to recognize that this is an area where we have a lot to do to help working people.”