On Wednesday, the committee was to take up a bill creating a temporary agriculture worker program.
"There has to be a first step, Mr. Chairman, and enforcing the law seems to me a reasonable place to begin," said Republican Rep. Trey Gowdy of South Carolina, who wrote the bill approved Tuesday.
Democrats called the bill a dangerous retread of a similarly tough enforcement measure that sparked mass protests around the country in 2006.
Reading the bill, "you would think there are 11 million criminals in the United States," said Rep. Luis Gutierrez, D-Ill.
The opposition among many House Republicans to sweeping action on immigration was on display Wednesday as Rep. Steve King, R-Iowa, an immigration hardliner, convened a six-hour press conference outside the Capitol to highlight opposition to the bill. People in the crowd held signs opposing "illegal aliens" and criticizing Sen. Marco Rubio, R-Fla., a conservative author of the Senate bill, as "Obama's Idiot."
Opposition in his conference to any immigration bill with a path to citizenship has put House Speaker John Boehner, R-Ohio, into a difficult position. On Wednesday, a day after trying to reassure House Republicans that he wouldn't bring immigration legislation to the floor without majority support from Republicans, Boehner was to meet with the Congressional Hispanic Caucus, which includes many liberal Democrats who are eager to see the House act on far-reaching legislation.
In the Senate, a bipartisan bill that Obama supports appeared on track for a final vote as early as July 4.
The CBO said in its report and accompanying economic analysis that the Senate legislation would raise economic activity in each of the next two decades, in part because of the legal immigration fostered by the measure and also because millions of workers currently in the country illegally would join the legal workforce and pay taxes.