Michael Bloomberg's surprise renunciation of his Republican affiliation makes it now likely, based on my unique experience with him, that he will run for president as an Independent (assuming that his mayoral predecessor is not the Republican nominee) and spend $2 billion in some 30 Blue or Purple states with 350 electoral votes.

Yes I'm the Mark Green who was his 2001 general election opponent. But I do think that Bloomberg has been a largely successful mayor who's a far more likeable person than 95% of the politicians I've met on both sides of the aisle. And yes it's expedient and opportunistic that he switched from being a life-long Demcorat to running as a Republican in 2001 merely to get on the ballot for mayor...and now switches again to get in position for an Independent candidacy for president. But opportunism apparently hasn't been a fatal flaw among politicians previously.

What's the principle here, other than personal ambition? The real principle here is that Mike's a businessman whose bottom line is not party or ideology but doing whatever it takes to get from here to there. Which will be very appealing to folks dismayed by ideological partisanship in Washington.

Every successful politician relives if not replicates his/her first campaign and victory in later campaigns. In April of 2001, Bloomberg said that he'd spend up to $30 million to win -- and anything more than that would be "obscene." But when he was behind me by 20 points at $30 million, he simply opened the spigot and spent $74 million to win by 2 points.

Conclusions: the chance he runs for president, high; his chance of winning, still infinitesimal because of Electoral College math; his chance of affecting the fall campaign, significant. Which way? It depends on whether he runs on more Democratic issues (anti-Iraq, global warming, guns) or on Republican stalwarts (balanced budgets, 9/11 and terrorism) -- while obviously also doing a pox-on-both-your-houses schtick that strikes a public nerve. Since Bloomberg's no fool and utterly uninhibited by party or philosophy or donors, you've got to figure that he'll run on proven popular Democratic issues such as universal quality health care, greening America, getting out of Iraq -- and "nobody owns me."

Unlike Perot, he has an estimable public record and is no loon -- so there's the real possibility that he could beat Perot's 19% in 1992 if the anti-everything, wrong-track public mood continues. While $2 billion in 2008 dollars is some 2000% more than Perot's $65 million, it's even more than that since the mayor is likely to spend it only in states that he could be competitive in -- i.e., states like Florida, New York, New Jersey, even Maine and Wisconsin. That means that his spending presidentially could possibly approach the $100 a vote he reached in 2001. (Bloomberg's not worth the $5 billion often reported but closer to $15 billion when his majority of stock in Bloomberg Inc. is taken into account.)

Can't win in a two-party America, you say. The last 3rd party candidate to win was Lincoln, and obviously Bloomberg's no Lincoln. Yes. But. Remember, nearly everyone told him that he couldn't win in 2001...and then voters got a mailing a day in three colors, couldn't watch a Yankee game without seeing an ad an inning, saw billboards in different languages in different communities. All Mike, all day. So when people tell him he can't win, he says to himself -- where have I hard that before?

So the bottom line for Mr. Bottom Line: if he thinks he won't embarrass himself and could break 19% nationally and more than that in swing states, he runs and takes 3 votes from the Democratic nominee for every 2 votes he takes from the Republican nominee. A guy who's only book is entitled Bloomberg by Bloomberg should not be underestimated.

Mark Green, president of Air America Radio, was the Democratic nominee for mayor against Mike Bloomberg in 2001.

My read on this is he is looking for a VP or President nood from the Demos.  Rockerfeller was Governor of New York and then VP—not a bad pre-retirement job--jk.