Of all the demographic groups in the United States, only one gave a majority of its votes to Republican candidates in Tuesday's elections for the House of Representatives.

The group is made up of people earning more than $40,000 a year. The pejorative phrase for them is "the rich".

Every other demographic group preferred the Democrats: the young, the old, whites, blacks, Hispanics, Catholics, Jews, Protestants, the poor, the middle class, white-collar workers, blue-collar workers, men and women.

Even among "the rich," support for Republican House candidates was tepid. They preferred them to the Democrats by only 50 to 47 percent.

These data are drawn from ABC surveys of 22,960 voters as they left 550 polling places across the nation. The sample was so large, according to ABC, that the margin for error is virtually nil.

The breadth of dissatisfaction with Republicans was striking in the ABC findings. It was reflected not only in the narrow demographic pigeonholes into which people are cast, but across the geographic spectrum as well: Sun Belt, Frost Belt, East, West, countryside and city.

This breadth of unease was not matched by its depth. That, along with local factors and personality, accounts for the Democratic failure to make greater gains in the House or to capture the Senate. Overall, ABC estimated that voters preferred Democratic to Republican House candidates by 57 to 40 percent, preferred Democratic Senate candidates by 55 to 43 percent, and preferred Democratic candidates for governor by 53 to 45 percent.

Two years ago, The Washington Post wrote of Ronald Reagan's election to the presidency: "The Reagan majority was . . . drawn from virtually every class in America, from every political persuasion, from every cultural and ethnic group . . . . The overriding reason for their choice, they said, was that 'it's time for a change.' "

Reagan in 1980 won a plurality of the voters under 30; on Tuesday they voted 6 to 4 for Democratic House candidates. Reagan in 1980 won a heavy majority among voters over 50; on Tuesday they voted Democratic nearly 6 to 4. Reagan in 1980 received more than 40 percent of the votes of labor union members; on Tuesday they voted almost 7 to 3 for Democrats.

The desire for change in 1982 was explicit in the interviews conducted by ABC. Unemployment, now at more than 10 percent, was identified by 43 percent of the voters as the nation's gravest problem.

The next most troublesome problem was inflation, given priority by only 17 percent of the voters. By contrast, only 3 percent expressed fears about the inadequacy of the American military establishment.

These priorities apparently found expression in congressional districts across the country with unemployment rates of 10 percent or more. In those districts, 61 of 101 Republican candidates were defeated.

Ohio offers an exaggerated example of what occurred in a number of races. An industrial state in which unemployment has been significantly higher than the national average for more than two years, Ohio has long had a Republican governor, who chose not to run in 1982.

ABC divided the Ohio electorate into 29 demographic and geographic categories. In all but two, the shift in votes to the Democrats exceeded 10 percent compared with the 1978 gubernatorial race. The shift among blacks and low-income voters was almost 20 percent. The smallest movement, 7 to 8 percent, was among farmers and high-income voters. Democrat Richard F. Celeste won by 6 to 4.

Some years ago John Kennedy remarked that while defeat is an orphan, victory has many fathers. This year, as in every election year, countless American interest groups are claiming shares of credit for the outcome. But given the broad support for Democrats in the absence yesterday of reliable information on voter turnout, it was difficult to assess special interest influences.

The AFL-CIO, for example, claimed that 63 percent of the House candidates it favored were victorious and that it was equally successful with Senate and gubernatorial candidates. Union members, the ABC polling data revealed, voted for Democrats by better than 2 to 1; as an entity they cast 4l percent of all the Democratic votes.

This means, of course, that nonunion members cast 59 percent of the Democratic votes. Who gets the credit?

There are further permutations. Women, ABC reported, cast 53 percent of the Democratic votes, blacks 15 percent, the elderly 19 percent, German-Americans 20 percent and Republicans 9 percent. Which voting blocs made the difference in specific races is unknown. But that is the essence of coalition politics; it leaves many IOUs outstanding.

One political lobby that will have difficulty collecting on IOUs in the days ahead is the National Conservative Political Action Committee. The ABC analyses showed that 18 of 19 House members NCPAC hoped to defeat were victorious. NCPAC's Senate scorecard shows one win and eight losses.

In several of the Senate races, according to Democratic pollster Peter Hart, NCPAC snatched defeat from the jaws of victory by creating sympathy for the candidates it opposed.

There is a final nugget in the ABC survey. On a day when Democrats were amassing a victory, when voters were unhappy with the economy and with Republicans, when 60 percent of the electorate hoped Ronald Reagan would not seek another term, the pollsters ran a trial heat on the 1984 election. It pitted Reagan against Edward Kennedy and against Fritz Mondale. Reagan won both times. Barely.