Promises of co-operation and invocations of bipartisanship fill the air. But the hard reality is that clashes will be frequent and inevitable between President George Bush and the incoming Democratic House and Senate in the next two years - a period that will be dominated by manoeuvring for the 2008 contest for the White House.
In the Oval Office yesterday, Mr Bush made temporary peace with the new masters of the House of Representatives, at a lunch with Nancy Pelosi, set to be the first female Speaker in US history, and Steny Hoyer, the second-ranking House Democrat who is likely to become majority leader.
As the President spoke to reporters about a "very friendly and constructive conversation," a beaming Mrs Pelosi - whose milder epithets about Mr Bush of late have included "incompetent" and "ignorant" - described the talks as "very productive". Asked by a reporter if she "could get on with this guy," she replied, "Certainly." She then stressed her impending responsibility to be Speaker not of the Democrats but of the entire House, in which her party will have a 29-seat majority.
A first test will come in what Mrs Pelosi has called a "100-hour programme," setting out her party's immediate goals as it takes command of the House for the first time since 1994.
They include the first increase in the minimum wage in nine years, to at least $7 (£3.70) an hour from the present $5.15, and moves to tighten ethics rules for lawmakers.
Thereafter, however, disputes loom over issues ranging from expanded stem cell research, which drew Mr Bush's only veto earlier this year, to the future of some of his tax cuts. Democrats have promised to rescind cuts benefiting the very rich but any such effort will be fiercely resisted by the White House.
The Democrat-run Senate will be equally troublesome. Mr Bush's appointees to key government jobs, and the federal bench are guaranteed much tougher confirmation hearings. Should a new vacancy occur on the Supreme Court, for instance, the President would have to put forward a moderate jurist, rather than the conservative he would prefer.
For that reason, the administration is bringing the two most important nominations of the moment to today's Republican-led "lame duck" Congress that will run until the 110th Congress opens in January. Bob Gates, picked to succeed Donald Rumsfeld, is set for speedy confirmation, if only because of the desire, shared by many Republicans, to be rid of the divisive Mr Rumsfeld as soon as possible. Indeed some bitter Republicans believe that, had his departure been announced before the election, their party might have been able to hold the Senate. Mr Gate's hearings were tentatively set yesterday for the first week of December.
The fate of John Bolton, the US ambassador to the United Nations, whose appointment runs only until the end of this Congress, is less certain. In an attempt to pre-empt a Democrat-controlled Senate Foreign Relations Committee, which would reject Mr Bolton, the White House re-submitted his nomination to the present Republican-led panel.
But everything depends on whether Lincoln Chafee, a committee Republican who reluctantly backed the blunt-spoken Mr Bolton in the past but lost his re-election battle on Tuesday, continues to support him. If not, the ambassador is doomed.
Even if Mr Bolton is confirmed, any warm feelings between executive and legislature are unlikely to survive investigative hearings promised by Democrats into such issues as the handling of Hurricane Katrina, the conduct of the war and the award of Iraq reconstruction contracts.
"If we tended to under-investigate, the Democrats will tend to over-investigate," Republican Congressman Tom Davis said, warning that "subpoenas will be flying".
If the experience of the 1994 Republican majority is any guide, the danger for Democrats lies precisely in such over-reaching. The Newt Gingrich-led Congress, perceiving Bill Clinton to be mortally wounded by that defeat, hounded the President on Whitewater and briefly shut down government in a battle on spending. The public sided with Mr Clinton, however, and he was handsomely re-elected in 1996. Alive to such danger, Mrs Pelosi has made clear that any attempt to impeach Mr Bush over Iraq would be "a waste of time". In fact, there are some promising areas for joint action, notably education and immigration.
How Republicans lost Latino vote on immigration
Of all the disasters the Republicans endured in the midterms, perhaps the most striking was the way the party alienated the fastest-growing part of the population - Latino voters.
Almost 70 per cent of Latinos voted Democrat, according to exit-poll estimates, fuelled by anger over the extremist position many Republican legislators have taken over immigration and by the disproportionate number of Latino men and women fighting and dying in Iraq.
George Bush came into office six years ago determined to woo Latinos nationally in much the same way he had as governor of Texas - appealing to their socially conservative instincts, promoting strong ties to central and South America and peddling a soft line on immigration policy.
That all changed a year ago, when Republican hardliners in Congress started to demand the criminalisation of the country's 11 to 12 million undocumented immigrant workers and the militarisation of the 2,000-mile border with Mexico.
President Bush ended up kow-towing to the hardliners, and his own party grassroots, by agreeing to the construction (but not the funding) of 700 miles of border fencing.
That stance infuriated even conservative lobby groups such as the Latino Coalition, which openly endorsed Democratic candidates for the first time.
Andrew GumbelReuse content