(CNN)Vermont Sen. Bernie Sanders is ready to strike.
The Democratic presidential candidate, who has been drawing thousands of supporters at rallies in early-voting states, is striking with contract workers Wednesday at the U.S. Capitol, in the fight to increase the minimum wage. He was joined by progressive caucus Democrats Rep. Keith Ellison and Rep. Raul Grijalva.
"It is a national disgrace that millions of full-time workers are living in poverty and millions more are forced to work two or three jobs just to pay their bills," Sanders said at the outdoor rally near the Capitol. "In the year 2015, a job must lift workers out of poverty, not keep them in it. The current federal minimum wage of $7.25 an hour is a starvation wage and must be raised to a living wage."
Sanders and the Congressional Progressive Caucus will introduce legislation that calls on Congress to enact a $15 an hour national minimum wage, as well as calling on President Barack Obama to issue an executive order that would reward companies with federal contracts if they agree to pay their workers $15 an hour, as well as allow them to unionize.
The minimum wage -- and the fight over wages in general -- has been a huge rallying point among liberals as Democrats have embraced the fight over income inequality.
Obama signed an executive order in February 2014 to raise the minimum wage for federal contract workers to $10.10.
But Sanders, the self-proclaimed Democratic socialist, and progressive members of Congress say that it's not enough.
"When I'm on picket lines around the country, people tell me they're protesting because they're working harder than ever and still can't make ends meet," Rep. Ellison tells CNN in a statement. "The Progressive Caucus stands in solidarity with the working Americans putting in longer hours and seeing smaller paychecks. In the richest nation in the world, no business should be able to pay so little their workers are forced to find second and third jobs to feed their kids."
Democratic presidential candidate Martin O'Malley released a statement last week, highlighting his endorsement of a $15 minimum wage increase and Hillary Clinton's declination to support the legislation.
"I strongly support the national movement to raise the minimum wage to $15 an hour, because it will lift millions of families out of poverty and create better customers for American businesses," O'Malley said. "Some people will say this is hard to do. And it will be. But leadership is about forging public consensus — not following it."
Clinton did not commit to supporting a $15 minimum wage increase and told Buzzfeed News Thursday that "there are different economic environments. And what you can do in L.A. or in New York may not work in other places."
Critics say that a $15 minimum wage increase will be disastrous for businesses, and in turn, for workers.
The Employment Policies Institute released an ad Wednesday slamming the legislation.
"This legislation is going to hurt employees is because it's completely unrealistic," Michael Saltsman, EPI's Research Director, told CNN in a phone interview Wednesday. "Customers are price sensitive and going to a $15 min wage is going to trigger businesses to take steps to off set higher costs."
Saltsman says that, as Sanders makes youth unemployment a key cornerstone to his presidential run, he "would say to him that raising the minimum wage to $15 an hour is worst thing because that's going to kick more [youth] out of a job."
With Congress under Republican control, there's little appetite to take up a legislative action to change the minimum wage, so at the national level there's not much that can be done beyond executive actions. However, at the state level, blue states and some cities have taken up the mantel of raising the wage on their own.