Bernie Sanders joins striking UAW workers on the picket line

Presidential candidate Bernie Sanders, the independent senator from Vermont, joined striking General Motors employees on the picket line in Detroit on Wednesday.

"I'm here today to thank you for having the courage to stand up to corporate greed," Sanders told the crowd.

Hovering at third place in most Democratic polls, Sanders is one of several presidential hopefuls expressing solidarity with the United Auto Workers. Massachusetts Sen. Elizabeth Warren, former Vice President Joe Biden and former Texas Rep. Beto O'Rourke visited striking members in Michigan, Kansas and Ohio, respectively.

The labor action is now in its 10th day, and in Detroit, a city long linked to auto manufacturing that's home to GM's headquarters, the future of the Detroit-Hamtramck Assembly Plant is uncertain.

GM announced in November that it was idling the factory, and with contract negotiations dragging, the option of producing new vehicles there could be a bargaining chip, according to the Detroit Free Press.

Wednesday afternoon, the automaker rejected Sanders' criticism of its wages and benefits.

"The total compensation of our UAW workforce – including wages, profit-sharing and benefits – is the highest in the U.S. auto industry," GM said.

Sanders made his show of solidarity a day after unveiling a sweeping plan for an American wealth tax that he said would slash the fortunes of billionaires in the U.S.

CLICK HERE TO READ MORE ON FOX BUSINESS