"They seem to be falling on the side of 'this is too much,' which is ironic from a bunch of New York City liberals," said Michael McKeon, a New York Republican political consultant. "Even for them, there seems to be a breaking point -- we just found it."

But for Bloomberg, none of this matters. His proposal would be implemented by a board of health stocked with his appointees, and he's a lame duck whose third and final term will end next year. Oh, plus, he's a zillionaire. More than anything, the uproar created by his soda restrictions serves to underscore the luxury enjoyed by the chief executive of America's largest city: Immunity to public opinion.

"The problem, for [his opponents], is that he doesn't care what people think of him. He just wants to do what he thinks is right," said Hank Sheinkopf, a Democratic strategist and sometime Bloomberg adviser. "This mayor has taken on the gun industry, the tobacco industry, the trans fat industry, whatever that is. He thinks it's his job to keep people alive, whether people like it or not."

Particularly now that his time in office is running out, Bloomberg operates with a measure of impunity unique among major American political figures. Call him "Nanny Bloomberg" all you want; as the soda controversy indicates, he's not afraid to push for unpopular policies on the assumption that eventually, a grateful populace will thank him for his foresight.

In an interview, the New York City Health Commissioner, Thomas Farley, said public opinion is important, but when it comes to health, it's not the most important thing.

"Sure, we care what people think, and we have reason to think a lot of people are supporting of this," he said. "The other thing, though, is that we have a board of health in New York City for a reason, and that is to take the issue of protecting the health of citizens out of the political process and put it in the hands of health experts."

You wouldn't respond to a cholera outbreak, he argued, by putting it to a vote, and "obesity is a crisis."

Farley and other supporters of the proposal -- which would make it illegal to sell most high-sugar-content drinks in sizes larger than 16 ounces -- point to Bloomberg's previous paternalistic initiatives, particularly his move to ban indoor smoking in 2003. The city has also, on his watch, forced restaurants to post health inspection ratings and calorie counts, and banned them from serving food with trans fats.

"All of them were seen as government overreach when they were put into place, and now New Yorkers can't imagine when things were otherwise," Farley said.

The smoking ban, initially the subject of an intense backlash from both the the public and the bar and restaurant industry lobby, now looks prescient, as jurisdictions across the U.S. and the world have banned indoor smoking to one degree or another. These days, even France and Ireland have smoking bans.