“April is the cruelest month,” T.S. Eliot warned, and particularly for Presi- dent Obama. The White House had been enjoying a robust run-up in the polls since the “shellacking” of Democrats in November’s midterm elections, but over the last month, Mr. Obama was back in freefall.

Six months ago, things looked bad for Mr. Obama. The Gallup daily tracking poll rated him at 43 percent approval and 49 percent disapproval. But this was the nadir of his fortunes. For the next five months, with the advent of Republican leadership in the House of Representatives and the mounting battles over the budget, the public seemed to rally to Mr. Obama. In mid-March, the Gallup survey had flipped, with 49 approving and 43 percent disapproving. Mr. Obama’s defensive strategy, letting the Republicans lead and then inflicting selective counterpunches, appeared to be working.

The worm has turned. In the last six weeks, the approval margin reversed again, and by the end of April, Mr. Obama was back to 43 percent approval and 49 percent disapproval in the daily survey, right back where he had been when he lost his supermajorities in Congress.

The reasons for Mr. Obama’s rapid decline are based in both perception and reality. Most Americans believe the economy is in serious trouble, and the anemic 1.8 percent spring gross-domestic-product figure tends to confirm that belief. The federal budget deficit continues to spiral out of control. Federal Reserve Chairman Ben S. Bernanke’s pledge to keep “transitory inflation” under control was met with skepticism, particularly as consumers see food and gas prices rising precipitously. Government economists omit food and energy from what they like to call “core inflation,” but average Americans don’t have the luxury of omitting them from their household budgets.

Mr. Obama gave a nod to the negative impact of gas prices at a California fundraiser on April 21. “My poll numbers go up and down depending on the latest crisis,” he said, “and right now gas prices are weighing heavily on people.” At the beginning of 2011, the average price of a gallon of regular gasoline was about $3. Now the price is over $4 per gallon in 12 states, including swing states that Mr. Obama won in 2008 such as Ohio, Michigan, Indiana and Wisconsin. Prices are highest in California at $4.22, and a USC/Los Angeles Times poll from early April showed his support there at 53 percent, down from a high of 65 percent. If California is coming into play, the election is truly up for grabs.

The Gallup weekly survey shows that support for Mr. Obama has for the most part dropped across the board since the middle of March. There were some signs of durable support from college graduates and liberal Democrats, and conservative Republican approval levels are steady - at 11 percent. Most surprising, and perhaps most alarming for the White House, are the disproportionate approval drops in key support groups. Approval from those aged 18-29 declined at twice the rate of the general population. Support in the eastern United States, an Obama bastion, dropped at a similar rate, as did support from nonwhites. Conservative Democrats and pure independents, important swing constituencies for the 2012 presidential race, also abandoned Mr. Obama at twice the national rate, and in the latter case, overall approval stands at 29 percent.

Demographic groups with historically higher voter participation rates - married people, those who attend church weekly, those aged 65 and older, and white voters - all rate Mr. Obama in the 30 percent range. This is not the stuff that re-election dreams are made of.