With the Capitol in the background, farm workers from West Palm Beach, Fla., march and chant while attending a rally for immigration reform Sunday on the National Mall in Washington.

Washington ? Frustrated with the lack of action to overhaul the country’s immigration system, tens of thousands of demonstrators rallied on the National Mall and marched through the streets of the capital Sunday, waving American flags and holding homemade signs in English and Spanish.

Supporters traveled from around the country in hopes the rally would re-energize Congress to take up the volatile issue. Some lawmakers oppose any attempt to help an estimated 12 million illegal immigrants become U.S. citizens while others insist on stronger border controls first.

President Barack Obama, who promised to make overhauling the immigration system a top priority in his first year, sought to reassure those at the rally with a video message presented on giant screens at the National Mall. The president said he was committed to working with Congress this year on a comprehensive bill to fix a “broken immigration system.”

Obama said problems include families being torn apart, employers gaming the system and police officers struggling to keep communities safe.

The president, whose comments were released as he worked to get last-minute votes on a health care overhaul, said he would do everything in his power to forge a bipartisan consensus on immigration reform. The House passed the landmark health care legislation late Sunday.

Lawmakers failed to agree in 2006 and 2007 when they last tried to overhaul the immigration system, and the political climate is even tougher now.

Sens. Chuck Schumer, D-N.Y., and Lindsey Graham, R-S.C., released an outline of a bill last week that calls for illegal immigrants who want to get on the path to legal status to admit they broke the law by entering the U.S., pay fines and back taxes, and perform community service. They also would be required to pass background checks and be proficient in English before working toward legal residency, required before becoming a citizen.

Ben Jealous, president of the National Association for the Advancement of Colored People and a speaker at the rally, said the activists no doubt got the attention of lawmakers by converging on the mall “on the one Sunday Congress was in session.”