President Michael Bloomberg?

Political bettors are hereby advised not to put the kind of money on the New York mayor’s chances that he might spend if he decides to make an independent bid for the White House.

But if mere speculation were gold, you could make a fortune on the number of words that will be devoted to that possibility over the next few months.

And despite the odds against success, the prospect of a Bloomberg bid adds an uncertain note to a presidential race already rife with maybes.

That’s inevitable in the wake of the billionaire’s decision to abandon the Republican Party he joined in 2001, when he realized he wouldn’t have Democratic support in his bid to become mayor.

As NBC Political Director Chuck Todd noted in his daily analysis, Bloomberg’s move ensures that pollsters will now ask about potential three-way races while he travels the country to gauge support.

And it would be hardly surprising if he found backing for a message that condemns the partisanship of the two major parties and promises a pragmatic, centrist approach to the nation’s problems. However, having the funds and an appealing message is a long way from mounting a successful third-party presidential bid. Ask Ross Perot.

It’s gotten easier to get your name on enough state ballots to be eligible for the 270 electoral votes needed to win the presidency; indeed, the proposed Unity08 party could prove to be a vehicle.

And whatever strength polls may initially show for an alternative to the major nominees, maintaining that support is a lot harder – unless you can show you have a real chance to win.

Some reports say Bloomberg won’t run unless he becomes convinced he can win. But that will be impossible to calculate by the time he’ll have to decide, regardless of the polls.

Historically, many voters who weigh the third-party option ultimately go with one of the major-party nominees as more likely winners. That happened to the last four major independent candidates: George Wallace in 1968, John Anderson in 1980, Perot in 1992 and 1996 and Ralph Nader in 2000.

It’s true that, along with unlimited personal funds, Bloomberg would bring a much-praised record as mayor of New York, no small achievement.

But there is doubt how much personal appeal the diminutive New York businessman would have to the millions of voters who live from the west side of the Hudson River to the Pacific Coast.

Indeed, there’s no certainty he’d win his home state. A Quinnipiac University poll last week showed that only 16 percent of voters would choose him in a presidential race against Democrat Hillary Clinton (43 percent) and Republican Rudy Giuliani (29 percent). The poll had a margin of error of plus or minus 3 points.

If he ran, he’d be more likely to influence the debate or help one or the other major party candidates. Initial speculation is split.

Greg Mueller, a top adviser to conservatives Pat Buchanan in 1992 and 1996 and Steve Forbes in 2000, predicted he would take more votes from Clinton or Sen. Barack Obama than from a conservative GOP nominee. Contending that many Democrats and independents oppose Clinton and consider Obama inexperienced, he said, “Bloomberg gives these voters a place to go, dividing the Democrat vote.”

But Todd’s daily NBC analysis predicts that a Bloomberg bid would help the Democrats by making them competitive in a three-way South.

My own sense is that Todd is right. A Clinton or Obama candidacy would have far more solid support from the Democratic base than most likely GOP candidates might have from a smaller GOP base already wary of them.

Bloomberg might also attract independents cool to Clinton, thus keeping them away from the GOP in swing states.

Under American University Professor Allan Lichtman’s theory of “presidential keys” that predict elections, a third-party candidacy is harmful to the incumbent party, in this case the Republicans.

And that’s what happened in 1912, 1948, 1968, 1980, 1992 and 2000. In five of those elections, the incumbent party lost and, in 1948, two independents damaged – but didn’t beat – Harry Truman.