Experts split over economy's impact on House, Senate races.

From the valley of this winter's recession, the view of the economy's impact on national elections this fall remains split.

Some political experts in both parties assert November's elections will be a ''referendum'' on President Reagan's economic program and on Republican performance in Washington.

Others say the economy will be recovering from the recession by election day, leaving the economic issue ''awash'' between lingering unemployment and fattening wallets.

Some political strategists say voters will cast ballots based on the national issue of economics. Others see a more local, candidate-based scenario for November's election, with the economy at most a backdrop or vehicle for taking a candidate's measure.

Survey data leave the economy's political role in 1982 unresolved. For congressional elections, how highly voters rank economic concerns such as unemployment and inflation appears closely linked to their choice of a candidate and his party. But other data show Americans largely satisfied, by a margin of 4 to 1, with how their personal lives are going - a reading that suggests recession and other economic negatives of the moment may be vivid concerns only for a minority of Americans.

In mid-January, 10 months from balloting, a state-by-state check on races for US Senate and governor reveals that an individual candidate's record or voter recognition count for more than any wholesale reading of economic trends, in the experts' rating of party prospects. This emphasis on candidate qualities and local context rather than broad national forces ''is always going to be the case nearly a year out'' from voting time, says Paul Maslin, voter analyst for Cambridge Survey Research, which handled President Carter's campaign and White House polling.

''This is not a national campaign yet,'' Mr. Maslin says, ''but it will be by next fall, both for federal and state offices, particularly in those states with the greatest economic concerns.''

''The intensity of feeling is increasing among voters feeling the recession's effect,'' Maslin says.

''The economy may turn around,'' he says. But he adds that even if it does, there is a time lag between the start of a recovery and a drop in unemployment.

''In 1982, we're going to have a referendum on the economy, and the President's and Congress's role in it,'' Maslin concludes.

Mel Larsen, chairman of Michigan's Republican Party, partly agrees.

''There is no question the outcome of (Michigan's) election is going to be tied to the economy,'' says Mr. Larsen. ''If inflation, unemployment, interest rates come down, we can win the Senate and retain governor seats. If not, it will be the year of the outsider - for Democrats or Republicans.'' In Michigan at least, where unemployment is the worst in the nation, Larsen sees continued economic problems hurting incumbents and candidates of both parties - Sen. Donald W. Riegel Jr. (D) and the GOP nominee for retiring Republican Gov. William G. Milliken's seat.

Ted Van Dyk, president of the Center for National Policy, a new Democratic think tank in Washington, argues his party cannot count on the recession for a free ride to success in November.

''The consensus forecast still is for a turnup by spring,'' Mr. Van Dyk says. ''Inflation and interest rates will turn down in May or June, unemployment will lag, but for three or four months the economy will show brief improvement - before turning down again in early '83.''

Van Dyk, with long Democratic experience including McGovern and Mondale presidential campaigns, predicts: ''We'll gain 10 to 20 seats in the House, because of normal off-year trends and generally soft Republican candidates. The Senate will be a stalemate. There will not be a shift.''

''Every off-year election is said to be a test of the (White House) incumbent's performance,'' Van Dyk says. ''This is not true. In the districts, a candidate's personality and character are far more significant than national trends.''

Wisconsin Republican Party chairman J. Michael Borden sees the economy having separate impacts on federal and state offices.

''The whole industrial belt from Philadelphia to Chicago is in tough shape,'' Mr. Borden says. ''We don't expect this to turn around until the middle of the year. If the economy is improving, if the voter thinks Reaganomics is working, Republicans will do well. If the economy is in tough shape, we won't.''

For the state legislative races, the local picture could be decisive. Wisconsin's GOP governor, Lee Dreyfus, up for reelection, came into office pushing $860 million in tax rebates. ''Now we are looking at a deficit,'' Borden says. ''The Democrats will try to pin it on Dreyfus. Republicans only picked up two seats in the state Legislature, while we were making a sweep in the federal Senate and House seats in 1980. Reagan won't have much of an effect in our state races. The governor will have more of an impact than the President.''