There were hints in Mr. Obama’s speech of potential fault lines in the debate. He declared, for example, that there must be a path to citizenship for illegal immigrants “from the outset.” That would seem at odds with the assertion by some senators that citizenship must be tied to tighter border security.
Although Mr. Obama did not say it in his speech, the White House is also proposing that the United States treat same-sex couples the same as other families, meaning that people would be able to use their relationship as a basis to obtain a visa.
Mr. Obama offered a familiar list of proposals: tightening security on borders, cracking down on employers who hire undocumented workers and temporarily issuing more visas to clear the huge backlog of people applying for legal status in the country.
His speech, on the heels of the bipartisan Senate proposal, sets the terms for one of the year’s landmark legislative debates. These are only the opening steps in a complicated dance, and the effort could still founder, as did the effort to overhaul immigration laws in the George W. Bush administration.
But the flurry of activity underscores the powerful new momentum behind an overhaul of the immigration system, after an election that dramatized the vulnerability of Republicans on the issue, with Mr. Obama piling up lopsided majorities over Mitt Romney among Hispanic voters.