Nancy Pelosi, a California Democrat, is set to be the first woman to head the 218-year-old House of Representatives as its speaker on Thursday. The speaker of the house is second in line to the presidency, after the vice-president.
Pelosi says she will clean up congress, which has seen multiple scandals in the past two years.
One of the first house votes will be to impose new restrictions on the relationship between lawmakers and lobbyists.
Marty Meehan, a Massachusetts Democrat who helped craft the ethics package, said: "No more taking gifts from lobbyists. No more lobbyists planning golf trips."
Keith Ellison, the first Muslim elected to the US congress, has generated controversy for his insistence on being sworn into office using a Quran instead of a Bible.
Critics argued that only a Bible should be used for the ceremonial swearing-in. And last month, Virgil Goode, a Republican representative, said that unless immigration is tightened, "many more Muslims" will be elected and follow Ellison's lead.
Ellison, a Muslim convert born in the US, will be sworn in as a Minnesota representative using a Quran from the Library of Congress. The Quran, published in London in 1764, was once owned by Thomas Jefferson, the third president and a founder of the country.
Bush tried to set a positive tone for dealing with the new 110th Congress, set to convene at noon EST (17:00 GMT) on Thursday. He called for spending cuts, a balanced budget and a consensus on Iraq.
"We hope that when the president says compromise, it means more than 'Do it my way,' which is what he's meant in the past"
Charles Schumer, New York Democratic senator
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"It's time to set aside politics and focus on the future," Bush said, who has two years remaining on his term.
Democrats were cautious.
Charles Schumer, a New York Democratic senator, said: "We hope that when the president says compromise, it means more than 'Do it my way,' which is what he's meant in the past."
Democrats won control of the House and Senate in elections on November 7, largely because of public discontent with the Iraq war and what critics called the "do-nothing" Republican Congress.
The Democrats' stated agenda includes: raising the federal minimum wage for the first time in a decade; cutting interest rates on federal student loans; ending some tax breaks for big oil companies and bolstering homeland security.