Yesterday, political strategist Mark McKinnon made the case that Sarah Palin's popularity could create an opening for New York City Mayor Michael Bloomberg to run for president in 2012. Well, that's original. Too bad it's preposterous. Katie raises two of the correct counterpoints: Bloomberg is uninspiring, and his Wall Street background doesn't seem like such a strong suit these days. But, she says, "McKinnon's argument shouldn't be discounted, and my quibbles aren't insurmountable hurdles for someone like Bloomberg."

Actually, McKinnon's argument should be dismissed out of hand, as there is no rationale for a third-party candidacy on the political, or policy, merits. Of course you can see why he made it. Like Bloomberg, McKinnon is a Democrat-turned-Republican but not a movement conservative. That describes a lot of rich white guys, who are overrepresented in the media. But it doesn't describe a lot of Americans, much less a plurality in a presidential election. McKinnon's thesis makes for a great web op-ed: it's pegged to Palin, but not a love-her-or-hate-her argument, and it works in the name of the billionaire New York mayor.

But, as the Gaggle's resident New Yorker, let me disabuse McKinnon and others who think Mike Bloomberg is popular in his hometown. He isn't. In 2001 he would have lost decisively to Mark Green despite spending $70 million on his campaign were it not for September 11 (the ensuing beatification of Rudy Giuliani turned his endorsement into gold). Bloomberg has governed effectively and yet he barely beat Bill Thompson, despite spending $100 million or so on his reelection campaign. Well, Barack Obama isn't Bill Thompson or Freddy Ferrer. He's brilliant, charismatic, had a well-run campaign that raised plenty of money, and he will have the advantages of incumbency. If Bloomberg were the Republican nominee, I'd bet heavily against him.

But that's not even the scenario McKinnon envisions. Nor should it be. The only idea more preposterous than Bloomberg beating Obama would be Bloomberg—a short, divorced, Jewish, socially moderate media mogul from New York by way of Boston—getting the Republican nomination. No, McKinnon thinks that if Sarah Palin is the Republican nominee in 2012 then Bloomberg could run as a third-party candidate.

While it is true that a Palin, or even a Mike Huckabee, nomination would leave moderate Republicans, both of them, out in the cold, there is no evidence that they amount to a larger constituency than the Republican or Democratic base. The oft-cited fact that the number of independents is growing is misleading. Most independents vote regularly for one party or the other. The days of one-party control of entire regions of the country, thus making the primary the actual election, are over, so there is no longer the same incentive to register with a party. But just because Southern conservatives and liberals battle it out in the general election instead of the Democratic primary doesn't mean the country is any more centrist.

What is more centrist than it was 40 years ago, though, is the Democratic Party. Bloomberg was a perfectly happy mainstream Democrat until he decided to run for mayor in a city where the Democratic field would be crowded. In New York, where unreconstructed Great Society liberals still roam, there may even be an ideological distinction between Bloomberg and some of his opponents. But look at his putative presidential platform: pro-abortion rights and gay rights, associated with racial harmony and welcoming of immigrants, concerned for the environment, committed to fiscal responsibility, combatting crime, and improvements in public education. That sounds an awful lot like the presidency of Bill Clinton, and what Barack Obama hopes to achieve.

If that's what Mark McKinnon wants he can just vote Democratic. The voters who fit this profile do not constitute any kind of majority. Split them from the minorities and other core Democratic constituencies in the blue and purple states where Bloomberg would have to exclusively focus and maybe you just throw those states to Republicans. Anyway, the idea that all of those voters would abandon Obama is absurd. What, exactly, does Bloomberg offer that Obama doesn't? Competence? That sure worked well for Mike Dukakis.