During the campaign, Mr Obama repeatedly promised to submit oil and gas companies to a profits windfall tax, citing the disparity between their huge profits and the struggles of ordinary Americans.
In the summer he said the tax would "help families pay their heating and cooling bills and reduce energy costs".
But the proposal has been quietly dropped from his agenda listed on transition team website's www.change.gov, setting off a storm of protest among liberal bloggers and small business groups.
An aide explained the change by saying: "President-Elect Obama announced the policy during the campaign because oil prices were above $80 per barrel. They are below that now and expected to stay below that."
But the shelving of the proposal was spotted by the California-based Small Business League, which asked if "the sudden elimination of this issue is a further indication that large corporations are already demonstrating their ability to influence the Obama administration".
"President-Elect Obama owes the American people an explanation as to why these campaign promises have been pulled from his agenda," it said.
The League was also disappointed that Mr Obama has dropped a reference that expressed concern that federal contracts designated for small businesses were being awarded to major corporations.
Mr Obama's decision follows indications that he will probably go back on another pledge - to introduce higher taxes for those earning $250,000 (£165,000) or more a year.
David Sirota, writing on the liberal blog Campaign For America's Future, said: "It seems like the Obama team is buying into the right-wing frame that raising any taxes - even those on the richest citizens and wealthiest corporations - is bad for the economy."
Mr Obama's emphatic victory on Nov 4 had left many of his liberal supporters hoping, if not presuming, that he will fulfil the parts of his agenda they most yearned for. This may not be the last time they are disappointed, as Mr Obama has so far shown an inclination to govern from the centre.
The oil industry, however, welcomed the move. It had argued that a previous windfall tax under Jimmy Carter cost the country billions as suppliers spurned domestically-produced oil and looked overseas.
"The judgment to withdraw the concept of a windfall profits tax is an important recognition that developing America's oil and natural gas would be seriously damaged by such a tax policy," said Lee Fuller of the Independent Petroleum Association of America.
Planners for Mr Obama's inauguration are meanwhile grappling with the sensitive issue of how celebratory the tone should be in light of the grim national economic mood.
There are normally numerous of gala and civic events in the days around the inauguration, but too much celebrity and glitz in the capital could look inappropriate to those struggling elsewhere.
Josh Earnest, a spokesman for the inaugural committee, said that while the depth of the crisis would be recognised, the inauguration "serves as a reminder that in these challenging times, our citizens want the kind of leadership that's going to galvanise the country".
Up to four million people are expected to flood Washington for the Jan 20 event, while more than 1,300 groups have applied to take part in the parade, compared to the 400 that applied for President Bush's second inauguration in 2004.