AP Photo/Charlie Neibergall An adviser for Sen. Bernie Sanders (I-Vt.) says the presidential candidate believes that "working people are key ... to what kind of economy we're going to have."

In a rare move for a major presidential candidate, Democratic hopeful Sen. Bernie Sanders (I-Vt.) joined a picket line with Verizon workers in New York City on Monday.

The decision to single out a major U.S. corporation by joining a worker protest is unusual for a serious presidential contender in the midst of a campaign. Sanders' camp believes the last major Democratic candidate to do so would have been Jesse Jackson in 1988.

“Let me get to the point,” Sanders said at the Monday picket line, which took place at a Verizon Wireless store in midtown Manhattan. “Middle class in this country is disappearing and what Verizon is doing to their workers is exactly what has got to be fought if we are going to rebuild the American middle class.”

"What this campaign is about is that corporate America can't have it all," he added.

Nearly 40,000 Verizon employees represented by Communications Workers of America union and the International Brotherhood of Electrical Workers are currently in a major contract battle with Verizon. CWA has also accused the telecom giant of retaliating against Verizon Wireless store employees who are union activists, charges that the company has denied.

Rich Young, a Verizon spokesman, said the company has been working since June to reach a "solid contract" with the workers, and he accused CWA of "distort[ing] facts."

"These PR stunts do nothing to help advance the bargaining process," Young told The Huffington Post, which is owned by Verizon. "Verizon remains ready to hold serious discussions and engage in meaningful negotiations that will result in a fair and balanced agreement. We truly hope union leaders are soon committed to the same."

While it may be unusual for a presidential candidate to join a picket line, it isn't unusual for the self-described democratic socialist from Vermont. Last year, before he declared his presidential bid, Sanders walked a picket line with workers at the telecom company FairPoint Communications, where 1,700 employees represented by IBEW were on strike in New England. He also marched with the Bakers, Confectioners, Tobacco Workers and Grain Millers Union Local 100G in Cedar Rapids, Iowa, last month.

"This is what we should demand of candidates who say they're for working people -- that they take a stand and that they're proud to do it," said Larry Cohen, a Sanders adviser. Cohen previously served as the longtime president of the CWA.

In a blog post at The Huffington Post on Monday, Cohen quoted from a message Sanders sent to Verizon employees in August, shortly before their contract expired: "I am hopeful you will reach a fair contract. But if you run into roadblocks, as in years past, know that I will be there with you until a fair contract is negotiated."

Now in NYC: @SenSanders stands w/ Verizon & Vzw workers fighting corporate greed #StandUp2Vz pic.twitter.com/kuXJvuU74R — CWA District 1 (@CWADistrict1) October 26, 2015

Sanders' long-running, vocal support for organized labor helps explain his appeal to many rank-and-file union members during the primary, even as frontrunner Hillary Clinton picks up more endorsements from establishment labor unions. Both candidates have placed economic inequality at the core of their campaigns as they seek the nomination, though it's much harder to imagine Clinton walking a picket line aimed at a telecom giant.

"Bernie believes that working people are key -- their standard of living, their jobs -- to what kind of economy we're going to have," Cohen said. "And that needs to be front and center and not something you get into obliquely."

This post has been updated with comments from Verizon.

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