Bush's approval rating, at 34 percent a week ago, tumbled on declining support from conservatives and Republicans. The poll found 52 percent of conservatives and 68 percent of Republicans approved of Bush's performance, record lows in both categories.

Bush's approval rating has been mired in the low and mid-30s in most surveys amid public unease about the Iraq war and rising gasoline prices. His plummeting standing has caused growing worry among Republicans about November's elections, when the balance of power in Congress will be up for grabs.

The poll of 1,013 adults, taken Friday through Sunday, had a margin of error of plus or minus three percentage points.