Back in April 2009, 74% of respondent in a CBS/New York Times poll said that letting the Bush tax cuts expire for those earning over $250,000 was a "good idea." Now 18 months later, even with President Obama's approval sliding and Congressional Democrats wavering in their commitment, the American public by large margins still supports ending the Bush tax cut windfall for the wealthy.
That's the word from Gallup. Its new survey conducted for USA Today found that:

A majority of Americans favor letting the tax cuts enacted during the Bush administration expire for the wealthy. While 37% support keeping the tax cuts for all Americans, 44% want them extended only for those making less than $250,000 and 15% think they should expire for all taxpayers.

And on this point, Democrats and independents are united:

That level of support for bringing an end to the gilded class payday is reflected in other recent polling. The question posed by late July survey from Pew Research/National Journal Congressional Connection produced similar results:

Which comes closer to your view about the tax cuts passed when George W. Bush was president? All of the tax cuts should remain in place. Tax cuts for the wealthy should be repealed, while others stay in place. All of the tax cuts should be repealed.
30% Keep all the tax cuts
27% Repeal the tax cuts for the wealthy
31% Repeal all the tax cuts
12% Unsure

Even Fox News showed majority backing the return of upper bracket tax rates to their Clinton-era levels. At the end of July, 36% favored continuing current rates for those earning under $250,000, while 14% backed allowing all of the Bush tax cuts to expire. As the Polling Report summary shows, a CBS survey conducted between August 20 and August 24 gave expiration this year for households earning about $250,000 a year or more a 20-point (56% to 36%) margin.
While McClatchy, AP and the Washington Post have documented the growing loss of nerve among Democratic lawmakers, Gallup concludes that opposing the $700 billion, 10-year giveaway to the richest Americans is a winning position for the President's party:

With about one in three Americans, including a minority of independents and Democrats, in favor of extending the Bush-era tax cuts for all taxpayers, Democrats may not be putting themselves at great political risk by allowing the tax cuts to expire for wealthy Americans. In fact, the middle ground of extending tax cuts for low- and middle-income Americans but allowing them to expire for wealthy Americans -- the Democrats' most likely proposal -- is the specific option the public prefers most.
Gallup has typically found Americans unsympathetic to the argument that upper-income Americans are overtaxed. They generally believe upper-income Americans pay too little in taxes and favor higher taxes on wealthy Americans as a means to fund government programs, such as Social Security.

Unsympathetic, with good reason. At a time of massive budget deficits and record income inequality, further draining the Treasury for the top 2% of taxpayers is bad policy. And as the pollsters confirm, bad politics as well.
(For more background, see "The Bush Tax Cuts in Pictures" and "10 Republican Lies About the Bush Tax Cuts.")