THE political amateur might be forgiven for thinking that the party that wins the most elections tomorrow fares best. But that's not the way Washington plays the expectations game - a game that involves manipulating the finish line while running the race.
Weekend handicappers from both political parties were predicting that the Democrats would pick up several House seats on Tuesday, with an outside chance of as many as a dozen. Odds were on no change in the Senate, with a possible Democratic gain of one.
So the result is a modest victory for the party that already controls both chambers of Congress.
Republicans point out, however, that this is an off-year election; the party that occupies the White House almost always loses ground in off-year elections.
Since the turn of the century, in fact, the out-party has gained an average of 34 House and 4 Senate seats in off-year elections, according to Congressional Quarterly records.
In spite of polls showing President Bush's popularity sinking (in the high 40s last week) and confidence in congressional Democrats rising, no one foresees Democrats performing up to the off-year average.
Rep. Guy Vander Jagt (R) of Michigan, chairman of the Republican National Congressional Committee, raises an even higher bar for the Democrats to leap.
This is the 10th year that Republicans have held the White House, he notes, and his party could set a record this year for staving off losses in 10th-year-of-same-party-in-White-House elections. The average gains by out-parties in such years, since 1870, is 39 House and 7 Senate seats.
By this measure, the apparent Republican rout Tuesday becomes a record-setting victory.
So the Democrats appear unlikely to measure up to historical patterns, only to slightly tighten their already firm grip on Congress.
Power is sharply divided already between a Republican president and Democratic Congress. Bush has only 176 Republicans in the House (40 percent) and 45 in the Senate (45 percent) - just enough, he has found, to sustain his vetoes.
President Eisenhower faced even bleaker arithmetic on Capitol Hill after the 1958 midterm elections, with 154 House and 34 Senate Republicans - just over a third in each chamber. Ford after Watergate found himself in a similar situation, with 144 House Republicans and 38 in the Senate. Ford had difficulty sustaining his vetoes - which can be overturned by a two-thirds vote in both chambers.
Republican politicos have discounted Democratic success in the past few years by arguing that Democrats would no longer control Congress if incumbents were not so insulated from competition.
The turnover rate has declined during the past dozen years: In the last House election, only 2.5 percent of incumbents who ran for reelection lost.
But not everyone ran for reelection. The total turnover rate in 1988 was 8 percent. House Speaker Thomas Foley (D) of Washington contends that 55 percent of the House turned over during the Reagan years, and 83 percent since Watergate.
He also argues that Republicans have more problems than just breaking through the incumbency barrier: Enough were elected during the Reagan years that - if they had all managed to hold onto their seats - the GOP would control the House.
Mr. Vander Jagt is already placing his hopes on 1992 when the pattern swings back in his party's favor. In presidential election years, the party of the winning president gains an average of 23 House and 3 Senate seats.
But when 1992 arrives, can the GOP win by just winning? Or will they have to beat the pattern?