(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.

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