The ad has $250,000 behind it and will run through Sunday nationally, and calls for a pathway to citizenship for immigrants who entered the country illegally.
Labor unions are a major force in favor of immigration reform, though tensions over a future guest-worker program Republicans and business groups see as a must-have could complicate the debate over the bill.
The ad warns that "there are some in Congress who reject this bipartisan proposal."
"They want to deny millions of hardworking Latinos a path to citizenship, keeping millions of Latino families in a state of uncertainty about whether they might still be separated," the ad continues. "But the power to make a difference is ours. They heard our voice in November — they'll hear it again today."