At the time, The Washington Post reported that Mr. Rubio’s advisers were monitoring to the minute how much time the hosts devoted to immigration, and that “they are heartened that the volume is much diminished.”Mr. Rubio publicly and privately worked to assuage the fears of Mr. Limbaugh, who on air called him a “thoroughbred conservative” and assured one wary listener that “Marco Rubio is not out to hurt this country or change it the way the liberals are.

”On Jan. 29, 2013, the same day Mr. Obama highlighted immigration in Las Vegas, Mr. Limbaugh had Mr. Rubio on as a guest to talk about immigration and called him “admirable and noteworthy” during a warm conversation about the bipartisan immigration plan.“I know for you border security is the first and last — if that doesn’t happen, none of the rest does, right?” Mr. Limbaugh lobbed.

“Well, not just that,” swung Mr. Rubio. “That alone is not enough.”The conversation concluded with Mr. Rubio saying: “Thank you for the opportunity, Rush. I appreciate it.”“You bet,” Mr. Limbaugh said.