New England Democrats have thrown their support behind a walkout of an estimated 31,000 employees of the Stop & Shop grocery chain. The workers, part of the United Food and Commercial Workers, went on strike Thursday following months of unsuccessful contract negotiations.

Sen. Elizabeth Warren, D-Mass, brought doughnuts to strikers at a Somerville, Mass., store on Friday. "@StopandShop workers deserve fair wages and good benefits—and I’m behind them 100% of the way. I stand in solidarity with @UFCW and the 31K workers who are making their voices heard," she tweeted.

Several members of the Connecticut congressional delegation endorsed it as well, including Democratic Reps. Rosa DeLauro and Joe Courtney and Sen. Richard Blumenthal.

The walkout appears to be one of the largest in recent years, according to the Labor Department, though its data tracking strikes doesn't include precise measurements of the number of workers involved.

.@StopandShop workers deserve fair wages and good benefits—and I’m behind them 100% of the way. I stand in solidarity with @UFCW and the 31K workers who are making their voices heard. https://t.co/mrQnKVWHU1 — Elizabeth Warren (@ewarren) April 12, 2019

UFCW claims that the parent company of Stop & Shop, Dutch conglomerate Ahold Delhaiz, is proposing cuts to the workers' contract that "would devastate health care benefits, significantly increase health care costs, and decrease take home pay." The changes include requiring workers to pay higher premiums for health coverage and reduced pension benefits, among other changes.

Stop & Shop contends that it "continues to offer excellent health care coverage" because "Associates’ share of health care premiums would remain well below national averages and increase only $2.00 to $4.00 per week each year."

The walkout was abrupt and a surprise to many customers for the chain, which is popular throughout New Jersey, New York and New England.

“All of a sudden, they announced over the intercom, ‘Stop & Shop is now on strike.' They said all the customers should drop their items and leave the store," shopper David Coughlin told the Brockton Enterprise.