US President George W. Bush, looking to energise his party days before key elections, was to step up his attacks on Democrats Saturday as opinion polls showed congressional Republicans are to take a beating.
In a rare departure from his routine, Bush was set to deliver his weekly radio address live from this Colorado town three days before voters were to go to the polls.
The US president is on a six-day campaign blitz aimed at shoring up vulnerable Republican candidates for the Senate and House of Representatives in 10 states that he carried in the 2004 White House race.
With the unpopular Iraq war the central concern on US voters' minds as Tuesday's vote nears, Democrats have cast the contest as a choice between a Bush's "stay the course" policy and "a new direction" under their stewardship.
"On this vital issue, the Democrats have taken a calculated gamble: They believe that the only way they can win this election is to criticise, and not offer a plan," said Bush said Friday in Le Mars, Iowa.
"So far they've have refused to tell us how they intend to win in Iraq and how they intend to secure this country. But there are four days left until the election, there's still time," he quipped.
Individual Democrats have floated various proposals on Iraq, where more than 2,800 US soldiers have died since the March 2003 invasion, but as a party they have broadly agreed on a phased withdrawal from the war-torn country.
Democratic Party chief Howard Dean later outlined his party's approach, making capturing or killing Osama bin Laden the top priority, and saying they would push to redeploy troops now in Iraq by withdrawing National Guard and Reserve units while keeping a "special operations" force to deal with terrorists.
He told CNN television that the Democrats wanted to "co-operate with other countries instead of try to bully them so we can get nuclear weapons out of the hands of the North Koreans. And be tougher on Iran."
"So we have a plan. The president hasn't shown us his plan. He didn't have a plan when he got into Iraq. He didn't tell the truth when he got into Iraq, and he doesn't know what to do now that he's there," Dean said.
A New York TimesCBS poll released Thursday showed only 29 percent of US voters approved of the way Bush is managing the war, equalling his lowest ratings from half a year ago.
All 435 seats in the House of Representatives, 33 in the 100-seat Senate and 36 state governorships are at stake. Democrats need to win 15 House seats to control that chamber and six seats to take the Senate.
The Rothenberg Political Report, an analytical firm in Washington, predicted Friday that Democrats will most likely to win from five to seven Senate seats and gain 34 to 40 seats in the House of Representatives. Bush also made two stops in Missouri as part of an 11th-hour political rescue mission aimed at galvanising the Republicans' conservative core supporters and make sure they vote on election day.
The president seized on figures showing the US jobless rate fell to a five-year low and said this vindicated the tax cuts he championed over Democratic opposition, many of which are due to expire in coming years.
"The tax cuts have led to a strong and growing economy, and this morning, we got more proof of that. The national unemployment rate has dropped to 4.4 percent. That is the lowest rate in five and a half years," he said in Springfield, Missouri.
Separately, US First Lady Laura Bush and Vice President Dick Cheney also criss-crossed the United States, looking to stir up Republican supporters.
But White House officials are worried about a slew of scandals, from corruption convictions to revelations that one Republican House member had a questionable relationship with teenage former House pages.
In the latest controversy, the White House-linked leader of an organisation that groups 30 million conservative evangelical Christians resigned amid allegations he bought sex and drugs from a male prostitute.
Asked whether this could depress turnout in a traditionally Republican constituency, White House spokesman Tony Fratto told reporters: "I doubt it."