"I think that health and age is fair game," Priebus said on "Meet the Press." "It was fair game for Ronald Reagan, it was fair game for John McCain."
Rove has spent much of the past week drawing attention to Clinton's late-2012 hospitalization for a blood clot. After he broached the subject at a conference in California earlier this month, Rove insisted that he never said Clinton has "brain damage" but said her age and health concerns could make her reluctant to launch a White House bid.
Priebus acknowledged that there probably isn't "a graceful way to bring up age, health and fitness for a candidate that wants to president of the United States," but he also said he doesn't view a Clinton candidacy as a sure thing.
"I’m not a doctor. What I do know is that the issue is going to come up as it does for any person running for president," Priebus said. "What I think is going to make her rethink whether she should actually run for president -- by the way, I don’t actually think she will if she has another month like she just had – but the issues that I talked about are going to be the issues that make her unacceptable to the American people."
Priebus expressed no such doubts about Clinton's desire to run a year ago, when the RNC publicly protested a pair of film productions on the former senator and first lady that were slated to air on NBC and CNN.
In letters sent last summer to NBC Entertainment chairman Robert Greenblatt and CNN president Jeff Zucker, Priebus said he objected to the productions "ahead of [Clinton's] likely candidacy for the Democratic nomination for president in 2016" and threatened to sever ties with the networks for the GOP's presidential primary debates.
NBC and CNN each ended up scrapping their planned productions.