Byron York

"Indeed, under your interpretation," the senators wrote in that letter to Napolitano and Clinton, "an able-bodied immigrant of working age could receive the bulk of his or her income in the form of federal welfare and still not be deemed a 'public charge.'"

Controversial in its own right, the question of government benefits for noncitizen immigrants has come up again in the debate over comprehensive immigration reform. In the early hours of Saturday, March 23, during the so-called vote-a-rama on amendments to the budget, the Senate rejected, by a vote of 56-43, a measure that would have denied access to Medicaid and, in coming years, to subsidies under Obamacare, for immigrants who came to the United States illegally but would be legalized through immigration reform.

The vote was almost entirely along party lines; Democrats voted against the amendment, and Republicans voted for it.

Sessions, an opponent of the so-called Gang of Eight bipartisan outline for reform, touted the vote as a milestone. "The Senate Democrat majority voted to extend free and subsidized health care -- specifically, Medicaid and Obamacare -- to illegal immigrants who could be granted legal status under any comprehensive immigration bill," he said. "The result of [this] vote places immigration reform in jeopardy."

That remains to be seen. But it is true that every Democrat on the Gang of Eight -- Charles Schumer, Richard Durbin, Robert Menendez and Michael Bennet -- voted against the amendment, while the Republican members of the Gang -- Marco Rubio, John McCain, Lindsey Graham and Jeff Flake -- voted for it.

Republicans in the Gang, especially Rubio, have repeatedly insisted that newly legalized immigrants will not be eligible for federal benefits under their comprehensive immigration reform proposal, and there's no reason to think they don't mean what they say. But the Democratic majority's vote on the Sessions amendment, plus the Obama administration's extraordinarily lax policy on benefits, suggests Democrats have very different ideas on the subject.

That could indeed place immigration reform in jeopardy. And even if comprehensive immigration reform becomes law with tough benefits restrictions in place, a Democratic administration will shape how it is enforced. Under almost any scenario, the benefits battle will last far beyond the current immigration debate.

Byron York

Byron York, chief political correspondent for The Washington Examiner