In the Senate, where Democrats previously held a 56-44 edge, Republicans quickly captured Democratic seats in Maine, Ohio, two in Tennessee (one of them previously belonging to Vice-President Al Gore), and Oklahoma, according to network televison projections last night, leaving them poised for the net gain of seven seats they needed for their first majority in the Senate since 1986.
One Republican disappointment came in Virginia, where CNN projected that the incumbent Democrat, Charles Robb, would be the victor in his bruising battle with Iran-Contra figure Oliver North. But Phil Gramm of Texas, the head of the party's Senate campaign committee, predicted a ``resounding victory'' with additional Republican gains in Michigan, Pennsylvania, Arizona and Nevada.
``I'm absolutely confident of a Republican majority in the Senate,'' said Mr Gramm. Another Republican strategist talked of a ``landslide''.
Among the rare crumbs of good news for the White House, the six-term Democratic veteran Edward Kennedy defeated his Republican rival Mitt Romney in their Massachusetts race. In the bitter Senate election in California, the costliest in US history, the incumbent Dianne Feinstein was leading the Republican Michael Huffington, who spent $27m (pounds 16m) of his own money on his campaign.
Republicans also have a chance of occupying a majority of the 50 state governors' mansions. George Bush's eldest son George Jr was doing well against incumbent Democrat Ann Richards in Texas. Another son of the former President, Jeb, was neck and neck with incumbent Lawton Chiles in Florida.
Exit polls put California's Governor, Pete Wilson, ahead of Democrat Kathleen Brown. Liberal standard-bearer Mario Cuomo, seeking a fourth term in Albany, was reportedly in a virtual deadheat with his little-known Republican opponent George Pataki in New York.
With an unusually high number of close contests, final results were not expected until late into the night. Much also depended on turnout which by mid-day was running well above levels for the mid-term of the Bush presidency in 1990. As the incumbent party facing a disenchanted electorate, Democrats were desperate for every vote to withstand the expected Republican advance.
Back in Washington after an eight-day, coast-to-coast swing, President Clinton gave a string of early morning radio interviews pitched at traditionally Democratic groups such as blacks and organised labour. ``This is not the time for negativism,'' he said, urging people to get out and vote.
But with Mr Clinton's personal unpopularity a heavy drag on Democrats, particularly in the South, the appeal was to little avail, and the White House was braced for the worst. Final opinion polls suggested that at least a dozen Democrat-held Senate seats were in serious danger, compared with at most three for their opponents.
In the House, the Republicans need to pick up 40 seats to overturn the previous Democratic margin of 256 to 178 - a large number but smaller than the mid-term swings against Presidents Ford, Johnson and Truman in 1974, 1966 and 1946 respectively. Senior Democrats have long been resigned to dropping 25 to 30 seats, the bulk of them in the South.
In a potential sensation, Speaker Tom Foley was said to be trailing early on in his Washington state district. Should he lose, Mr Foley would be the first Speaker to suffer such ignominy since 1860. In a bellwether Indiana House seat, incumbent Democrat Jill Long was heading for defeat at the hands of Republican Mark Souder.
But even if the Republicans fail to take outright control in either chamber, both will be markedly more conservative than their predeccessors, with virtual veto power over legislative proposals from the White House. That in turn will make Mr Clinton's bid for re-election in 1996 even tougher.
In yesterday's vote, all 435 House seats, 35 of the 100 Senate seats, and 36 of the 50 governorships were at stake. Though they have no direct role in Washington, governors control powerful state party organisations, which can be decisive in presidential elections.
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