President Bush asked Congress Monday for the second half of the controversial $700 billion financial bailout fund after President-elect Barack Obama asked him to do so, the White House said.

Underlining the delicate politics of the issue, one of Obama’s top economic advisers followed up with a letter to congressional leaders promising changes in how the bailout program is handled, including placing more emphasis on relief for struggling homeowners and stricter accountability for how the money is spent.

Bush’s notification to Congress is expected to spark an intense round of jockeying over the funding in the face of widespread dissatisfaction among lawmakers over how the first $350 billion was spent and accounted for.

Bush, at his final news conference before he leaves office Jan. 20, said, “I have talked to the president-elect about this subject. And I told him that if he felt that he needed the $350 billion, I would be willing to ask for it.”

Lawrence Summers, Obama’s top economics adviser, said in his letter to congressional leaders that Obama believes the need for the new funding is “imminent and urgent. We cannot afford to wait.”

The spotlight now shifts to Congress, where a nasty battle is brewing between supporters of a new round of funding and lawmakers who have assailed the way Treasury allocated the first half.

Congress will have 15 days to block release of the remaining $350 billion through a resolution of disapproval. But even if Congress clears a disapproval resolution, it could be vetoed, meaning that each chamber would have to come up with a two-thirds majority to override a veto and block release of the money.

Obliquely acknowledging the political climate on Capitol Hill, Bush suggested that “the best course of action, of course, is to convince enough members of the Senate to vote positively ... for the request.”

Obama’s team is already focusing its lobbying efforts on the Senate. Anti-bailout sentiment remains intense in the House, and that chamber could well pass a resolution of disapproval by an overwhelming margin.

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