Former New York Mayor Rudy Giuliani (R) endorses his eventual successor, former Mayor Michael Bloomberg (I), in 2001. AP/Robert Spencer Former New York City Mayor Rudy Giuliani (R) has some interesting theories about his successor potentially launching a 2016 Democratic presidential campaign.

In a Fox Business interview on Wednesday, Giuliani said "there's room" for former New York City Mayor Michael Bloomberg (I) to make it into the race as a Democrat.

However, Giuliani also noted the billionaire media mogul would have to battle against a fellow "centrist" Democrat: former Secretary of State Hillary Clinton.

"It makes a lot of sense. I mean, there are two wings in the Democratic Party, like there are various wings in the Republican Party. Let's call it the 'progressive' and the 'more centrist' wing. Hillary, for better or for worse, right now represents the 'centrist' wing," Giuliani said.

Giuliani was responding to a question about a Wednesday report by New York Post columnist Michael Goodwin. In the column, Goodwin claimed some New York Democrats are urging Bloomberg to switch his political party from independent to Democratic and challenge Clinton for the nomination. Bloomberg reportedly expressed interest in the idea.

Giuliani suggested a Bloomberg 2016 campaign could embolden other Clinton foes in the Democratic Party as well. He cited Sen. Elizabeth Warren (D-Massachusetts) and current New York City Mayor Bill de Blasio (D) as potential "progressive wing" contenders. Warren has repeatedly insisted she has no interest in the race. De Blasio recently tried to make national waves as a progressive leader but has also said he's not running.

"Elizabeth Warren is the big representative of the 'progressive' wing; de Blasio, I think, wants to be. There's room for Michael Bloomberg," Giuliani said. "Plus, here's the interesting thing. If he entered the race against Hillary, … that would divide up the centrist vote and I think that might change up Elizabeth Warren's mind. ... Hillary and Mike would kind of divide the same Democratic vote. And the progressives would be sitting on the outside, and Elizabeth Warren or de Blasio or somebody like that could have a chance." (Giuliani offered a skeptical laugh when he said de Blasio's name.)

Former New York City Mayor Rudy Giuliani (R) on Fox Business. Fox Business

Giuliani also noted Bloomberg would face some difficulties in the Democratic primary. Notably, he said, Bloomberg held office as both a Republican and as an independent, which would result in his being labeled a turncoat if he ran.

"He's got issues — nothing to do with the way he governed; I thought he was a terrific mayor. He has issues about changing parties: He was a Democrat, became a Republican, became an independent, and still is not a Democrat as far as I know. So that always hurts you," Giuliani said.

Of course, there's nothing new about the quadrennial rumors that Bloomberg will launch a campaign for the White House. Other recent speculation has included a potential mayoral campaign in London. Many veteran observers have rolled their eyes at the various rumors, however.

Additionally, sources at his eponymous company confirm that, since leaving City Hall, Bloomberg has been very involved in the day-to-day operations of his business. He has also been engaged in restructuring several areas of the company.

Watch Giuliani's Fox Business interview below: