CHICAGO (CBS) — As Republicans in the U.S. Senate prepare to repeal the Affordable Care Act this week, rallies were held Sunday throughout the country in opposition of that plan.

In Chicago, hundreds gathered inside the SEIU Healthcare Illinois Headquarters, while others rallied outside of the building. Their message was conveyed through a number of signs and chants: repealing the ACA could be disastrous for the American people.

Senator Dick Durbin said the move would put Illinois residents at risk. WBBM’s Andy Dahn reports.

“Now we’re in a debate in Washington,” Durbin said. “The first issue of the Republican Congress is to repeal the Affordable Care Act. What does that mean right here in Illinois? 1.2 million people will lose their health insurance.”

Several other political leaders, including Cook County Board President Toni Preckwinkle and State Rep. Jan Schakowsky spoke at the rally, criticizing President-Elect Donald Trump for supporting repealing President Obama’s signature legislation, without a concrete plan to replace it.

Durbin called the turnout “overwhelming” and “exceptional” and said it sends a strong message to those behind the planned repeal.