Despite an apparent effort to assume the political payback for a blood-soaked month of US combat deaths and Iraq's slump into sectarian strife, Mr Bush refused to admit defeat to surging Democrats ahead of November 7 polls.
"If you are asking about accountability, it rests right here --- that's what the 2004 campaign was about ... if people are unhappy about it, look right to the president," Mr Bush said at a White House press conference.
"The American people are going to decide ... based upon who (is) best to protect the American people and who (is) best to keep their taxes low," he said.
"This campaign has obviously got national implications to it, no question about it ... but each of these elections turn out to be local in their scope and in their character."
With voter anxiety soaring over Iraq, Mr Bush also assured Americans he shares their frustration, as Republicans face a desperate two-week final sprint to cling to control of both chambers of Congress.
"I know many Americans are not satisfied with the situation in Iraq -- I'm not satisfied, either," Mr Bush said, and offered a new vow of support for Defence
Secretary Donald Rumsfeld, a lightening rod for Democrat attacks on Iraq.
"We cannot allow our dissatisfaction to turn into disillusionment about our purpose in this war," Mr Bush said, stressing that victory was vital to US security in generations to come.
The White House has struggled to define the debate in recent days, dropping the formulation that US troops must "stay the course" in Iraq for a message that tactics are not frozen but constantly evolving to match the threat.
Mr Bush spoke after a series of bombings, sectarian killings by death squads and unrest in Iraq, which killed more than 90 soldiers and many more Iraqi civilians.
A CNN poll published on Tuesday found that only one in five Americans believes the United States is winning the war in Iraq. Eighteen percent believe insurgents are winning, but the majority, 60 percent, say no one is winning in
Iraq.
The latest ABC News/Washington Post poll found that the elections would be a referendum on the Iraq war, and that 57 percent of voters said it was not worth fighting.
Turning up the campaign-trail rhetoric, Mr Bush mocked rival Democrats he said were already sizing up top congressional offices, and taking victory for granted.
"We've got good candidates, running hard, and we're going to win ... I know that defies conventional wisdom," he said, and accused his rivals of prematurely "dancing in the end-zone," an American football metaphor.
"They're going over to the Capitol, and saying 'my new office looks beautiful, I think I'm going to have this size drape there, or this colour.'"
Democrats immediately went on the counter-attack, with Senate Minority leader Harry Reid claiming "the Bush administration's Iraq policy, like Iraq itself, is in disarray."
"It is increasingly clear that the president does not know what to do to stop the escalating violence."
Senator John Kerry, who lost to Mr Bush in the 2004 presidential election, charged that the president was "working overtime to change his rhetoric on Iraq when we need him to change his policy."
"Our heroes are paying the price for the president's pride and stubbornness."
Democratic party strategists have used voter anger over Iraq as a prominent theme in their campaign advertisements and rhetoric.
Some Republican candidates have even sought to distance themselves from the president as Iraq roils congressional races from coast to coast.
Democrats need to gain 15 seats in the House of Representatives and six in the Senate to win control of Congress and opinion polls show support for Republicans has eroded to its lowest point since their watershed 1994 conquest of the two chambers.