----- — The White House issued a statement that said it welcomed "the process moving forward in the House, and we look forward to working with all parties to make immigration reform a reality."
Rep. Nancy Pelosi, D-Calif., the leader of House Democrats, said she hoped it was possible to find common ground. Yet she added that the Republican principles "raise more questions than answers," including on the sensitive issue of citizenship.
The entire subject remains intensely controversial, particularly among conservatives in both houses of Congress.
Rep. Steve Scalise, R-La., who heads the Republican Study Conference, a group of conservative lawmakers, repeatedly declined to say on Thursday whether there were any circumstances under which he would be able to support legislation that bestowed legal status on adults currently living in the country illegally.
Another Republican, Rep. Jason Smith of Missouri, told reporters that his constituents "definitely have big concerns about legalization."
The drive to overhaul immigration laws flagged after the Senate acted, as House conservatives dug in. The House Judiciary Committee has approved four bills, but none has reached the House floor as conservatives have expressed concern about being drawn into an eventual compromise with the White House.
One of those bills would toughen enforcement of immigration laws, including a provision that would permit local police officers to enforce them as part of an attempt to raise the number of deportations. It also would encourage immigrants in the United States illegally to depart voluntarily, an echo of Mitt Romney's call for "self-deportation" in the 2012 presidential race.
Other measures would create a new system for requiring employees to verify the legal status of their workers, establish a new temporary program for farm workers and expand the number of visas for employees in technology industries.