Sen. Elizabeth Warren (D-MA) is working to elevate her status as one of the most outspoken pro-union presidential candidates and is expected to join teachers in Chicago on Tuesday as part of their ongoing strike, visiting a South Austin elementary school and “picketing with teachers and American Federation of Teachers President Randi Weingarten,” according to local reports.

Thursday marked the first day of the Chicago Teachers Union (CTU) strike, resulting in the cancellation of classes for the 361,000 K-12 students who attend Chicago Public Schools (CPS). The union and CPS have been unable to reach a negotiation on numerous issues, including salaries, benefits, and classroom size.

Warren is expected to join them as they go into their fourth day of the strike.

NBC Chicago reports:

According to a campaign email, the stop in Chicago will be part of a two-stop swing for the Democratic presidential candidate on Tuesday. Warren will join striking teachers in Chicago at a South Austin elementary school on the city’s West Side, picketing with teachers and American Federation of Teachers President Randi Weingarten.

Warren has made tangible efforts to position herself as one of the most outspoken pro-union 2020 candidates, joining airport food workers in a minimum wage protest at Reagan National Airport in July:

On Labor Day, Warren called for “stronger unions” and declared that unions will “rebuild America’s middle class.”

“Unions built the middle class—and unions will rebuild the middle class,” Warren wrote. “If we want more good American jobs, then we need stronger unions and more power in the hands of the people”:

Unions built the middle class—and unions will rebuild the middle class. If we want more good American jobs, then we need stronger unions and more power in the hands of the people. I’m proud to be fighting alongside our unions. #LaborDay pic.twitter.com/uoAqIq9tH2 — Elizabeth Warren (@ewarren) September 2, 2019

No matter how many times strikers and organizers have been told "it’s too hard, give up now," they've persisted. When workers organize and fight together, they win—and they can change America. #LaborDay pic.twitter.com/0dVQuz4wWz — Elizabeth Warren (@ewarren) September 2, 2019

I’m in this fight for America’s workers every step of the way. #LaborDay pic.twitter.com/NDK8iohEOp — Elizabeth Warren (@SenWarren) August 30, 2019

Coming out of the Great Depression, labor unions helped build America’s strong middle class. As our families got richer, our country got richer – & labor unions were a big part of it. Today, unions are under attack, & we need to fight back so workers can make their voices heard. pic.twitter.com/kM66Rb3CRg — Elizabeth Warren (@SenWarren) September 1, 2019

Happy #LaborDay! Today we say loud & clear: unions built America’s middle class, & unions will rebuild America’s middle class. pic.twitter.com/GbzfDsa914 — Elizabeth Warren (@SenWarren) September 2, 2019

As for the CTU, negotiations are still underway, but progress, according to CTU President Jesse Sharkey, has halted. Sharkey accused Chicago Mayor Lori Lightfoot’s administration of “vindictive actions” and added that her recent letter “dashed our hopes of a quick settlement,” according to the Chicago Tribune.

According to the report:

Sharkey’s accusation came after Lightfoot and Chicago Public Schools CEO Janice Jackson made a plea to teachers to end their strike before a settlement and continue negotiations while working without a contract, leading Sharkey to say after negotiations ended for the day that Lightfoot’s letter had “dashed our hopes for a quick settlement.”

Sharkey said in an email that their bargaining team was “beginning to see glimmers of progress on issues that matter to our members” but added that progress “stopped dead” on Monday.

“It was clear from the mayor’s letter to the press demanding members go back to work without a contract and from the sudden atmosphere of stonewalling from the CPS team, that (Mayor Lori Lightfoot) had pulled the plug on negotiations,” Sharkey wrote, according to the Chicago Tribune.

“The mayor’s team said that there was no more money in the budget to address the many outstanding demands that are necessary to deliver justice for our school communities,” he added.

While Lightfoot and CPS CEO Janice Jackson have said that “real progress” was being made, both made it clear that the strikes are hurting students.

They wrote:

For the fourth straight school day, students from throughout the city won’t be participating in the athletic competitions they’ve earned the right to compete in, won’t be preparing their college applications with trusted school staff, and won’t be in classrooms with the teachers who hold the keys to their success.

“We must fix that immediately and end this strike,” they added.