Washington — As the congressional election season moves into its final days, the economy is providing campaign ammunition for both sides.
The administration is hailing September's consumer price index, which shows that during 1982 prices may rise less than in any year since 1972. But along with Tuesday's good news on inflation came word that during September, production workers' wages after adjustment for inflation continued to fall, by 0 .3 percent. Meanwhile, unemployment remains at record levels and the stock market is trying to recover from its biggest one-day dip since 1929.
With the US economy in the doldrums, upward pressure on consumer prices is clearly ebbing. And economists see little chance that inflation will reignite in 1983.
''Inflation is still very much on the descent,'' says Irwin Kellner, senior vice-president and chief economist at Manufacturers Hanover Trust Company. ''And there are many more months of good numbers ahead before there is any threat of bad numbers.''
Consumer prices rose only 0.2 percent in September, the Labor Department says , which works out to a seasonally adjusted annual rate of 2.1 percent. For the year to date, prices have risen 4.8 percent.
Inflation reports for the rest of 1982 could be even better, some economists say, as declines in home prices and mortgage rates are factored into the consumer price index.
''As we move through November and December the [inflation] rate could be close to zero,'' notes Ted Gibson, vice-president and senior economist at Crocker National Bank in San Francisco. As a result, the inflation rate for all of 1982 could drop below 4.8 percent. The last time that happened was in 1972, when prices rose 3.4 percent.
President Reagan was quick to take credit for the inflation outlook. Before leaving Washington for a campaign trip to North Carolina, the President told reporters, ''Since all of you seem to feel I'm to blame for unemployment, I'll take the credit for this.''
House Speaker Thomas P. O'Neill Jr. said the consumer price figure ''is nothing to brag about. It is the direct result of the worst recession since the 1930s. Of course prices are not rising as fast as they were; no one is buying anything.''
Even the President's supporters are not sure what impact the improved inflation picture will have on the congressional elections. ''The political signficance of the trend is difficult to assess,'' says Jerry Jasinowski, chief economist of the National Association of Manufacturers, a business group that supports Reaganomics. ''Polls continue to show that two-thirds of the people don't recognize there has been a change in inflation.''
Lower inflation has already been factored into Wall Street's investment strategy. So the most recent inflation data are not expected to have a significant effect on the stock market correction which began Monday when the Dow Jones industrial average dropped 38.33 points, its biggest one-day decline since 1929. The drop represented about 3.5 percent of the market's total value, compared with 12.82 percent on ''black Monday,'' Oct. 28, 1929. Yesterday, stock prices were also moving down substantially.
Analysts offer a variety of reasons for the market's decline. ''We had a very substantial move in the market - 250 points on the Dow - without a correction,'' explains Monte Gordon, research director at the Dreyfus Corporation, a mutual fund manager. And investors were disappointed that the Federal Reserve Board did not lower the discount rate last Friday. The discount rate is what the Fed charges commercial banks for funds they borrow from it.
Although the market may move lower for several weeks, most analysts expect the bull market to continue. ''There are so many people who missed the market that I just don't see (the correction) lasting too long,'' says Robert Stovall, senior vice-president of Dean Witter Reynolds, a brokerage firm. ''This just delays our making an all-time high from October to sometime later in the year or early in 1983.''
Some of the decline in the inflation rate may overstate economic reality, forecasters say. ''We are getting unsustainably low price increases due to what is happening to home prices and mortgage rates,'' says Sandra Shaber, senior economist at Chase Econometrics, a forecasting firm. But she expects inflation in 1983 to run in the 5 to 6 percent range.
There are a variety of reasons economists expect that inflationary pressures will not take off next year. ''The weak economy is reason No. 1,'' says Mr. Kellner at Manufacturers Hanover. He notes that large amounts of excess production capacity make companies less likely to raise prices. And high unemployment tends to moderate wage demands. In addition, relatively few major union contracts will be negotiated in 1983.
Also holding down inflation is the fact that commodity prices have fallen some 30 percent from their 1980 highs, Kellner notes.
Still, economists sound a note of caution. ''Inflation may be down but it is not out,'' Kellner says.