Rudy Giuliani was a close adviser to Donald Trump throughout his White House bid. | Getty Source: Giuliani narrow favorite for secretary of state

Former New York City Mayor Rudy Giuliani is the narrow favorite to be Donald Trump’s secretary of state, a source close to the president-elect told POLITICO Tuesday morning.

Giuliani was a close adviser to the Manhattan billionaire throughout his White House bid and is a vice chairman of his transition team’s executive committee. A former U.S. attorney and associate attorney general, he was previously thought to have been under consideration to lead the Department of Justice or the Department of Homeland Security.

That Giuliani could be tapped to lead the State Department was first reported by the Associated Press. Asked if the former New York City mayor would be nominated to the post, Trump’s former campaign manager Kellyanne Conway was noncommittal.

“He could be. He certainly is a very close adviser of President-elect Trump’s,” she said on NBC’s “Today.” “The mayor has an enormous skill-set, would be an excellent member of the cabinet and that's where I’ll leave it.”

While Giuliani has regularly discussed law and order issues as a surrogate for Trump’s campaign, foreign policy is a topic he has been asked about less. But he is a regular world traveler for his private-sector work, which includes advising foreign governments on security issues. He is also a partner at the law firm Greenberg Traurig.