According to documents obtained by CBS News and The Associated Press, the senators will call for accomplishing four goals:

-Creating a path to citizenship for illegal immigrants already here, contingent upon securing the border and better tracking of people here on visas.

-Reforming the legal immigration system, including awarding green cards to immigrants who obtain advanced degrees in science, math, technology or engineering from an American university.

-Creating an effective employment verification system to ensure that employers do not hire illegal immigrants.

-Allowing more low-skill workers into the country and allowing employers to hire immigrants if they can demonstrate they couldn't recruit a U.S. citizen; and establishing an agricultural worker program.

The principles being released Monday are outlined on just over four pages, leaving plenty of details left to fill in.

What the senators do call for is similar to Mr. Obama's goals and some past efforts by Democrats and Republicans, since there's wide agreement in identifying problems with the current immigration system.

The most difficult disagreement is likely to arise over how to accomplish the path to citizenship.

In order to satisfy the concerns of Rubio and other Republicans, the senators are calling for the completion of steps on border security and oversight of those here on visas before taking major steps forward on the path to citizenship.

Even then, those here illegally would have to qualify for a "probationary legal status" that would allow them to live and work here -- but not qualify for federal benefits -- before being able to apply for permanent residency. Once they are allowed to apply, they would do so behind everyone else already in line for a green card within the current immigration system.

That could be a highly cumbersome process, but how to make it more workable is being left to future negotiations. The senators envision a more streamlined process toward citizenship for immigrants brought here as children by their parents, and for agricultural workers.

The debate will play out at the start of Mr. Obama's second term, as he aims to spend the political capital afforded him by his re-election victory on an issue that has eluded past presidents and stymied him during his first term despite his promises to the Latino community to act.

"As the president has made clear for some time, immigration reform is an important priority and he is pleased that progress is being made with bipartisan support," a White House spokesman, Clark Stevens, said in a statement. "At the same time, he will not be satisfied until there is meaningful reform and he will continue to urge Congress to act until that is achieved."

For Republicans, the November elections were a stark schooling on the importance of Latino voters, who voted for Mr. Obama over Republican Mitt Romney 71 percent to 27 percent, helping ensure Obama's victory. That led some Republican leaders to conclude that supporting immigration reform with a path to citizenship has become a political imperative.