Without directly suggesting some sort of bargain to reduce the charges Mr. Snowden faces and perhaps pave the way for his return from exile in Russia, Mr. Paul said, “I think the only way he’s coming home is if someone would offer him a fair trial with a reasonable sentence.”

But a leading Democrat, Senator Charles E. Schumer of New York, took a directly opposing view.

“I disagree with Rand Paul that we should plea-bargain with him prior to him coming back,” Mr. Schumer said.

The New York senator appeared after Mr. Paul on the ABC program, where both men were asked about a New York Times editorial about Mr. Snowden that cited “the enormous value of the information he has revealed, and the abuses he has exposed,” and suggested that the United States offer Mr. Snowden a plea bargain or some form of clemency.

Calls for leniency, which have also come from groups like the American Civil Liberties Union and from commentators at home and abroad, have been fueled by a federal judge’s ruling that one of the surveillance programs Mr. Snowden exposed was probably unconstitutional.

But Mr. Schumer said that if Mr. Snowden considered himself part of the “grand tradition of civil disobedience in this country” — a tradition he said included the Rev. Dr. Martin Luther King Jr. and Daniel Ellsberg, who leaked the Pentagon Papers four decades ago — he should return to stand trial and face the consequences of his actions. Such a trial, the senator said, could be enlightening for the country.