CAMPAIGN SPENDING IN CONGRESS RACES SOARS TO NEW HIGH

Congressional campaign spending has soared to record levels this year as far more lawmakers than usual face tough fights to hold on to their seats, Federal Election Commission records show.

The trend is apparent in races for both chambers but is especially obvious in campaigns for the House. In past years incumbency has almost guaranteed re-election for House members, but in 1992, voter hostility, aroused in part by some lawmakers' abuse of checking-account privileges at the House Bank, has frequently made it an obstacle.

In addition, many House members are spending more trying to appeal to substantial numbers of new voters because of redistricting. Hurt by Recession

The increase in spending has not been matched by an increase in fund raising, largely because political action committees, which dole out money on behalf of industries, trade associations, unions and ideological groups, have given only a little more than in past years. The committees, which have often been accused of having an excessive influence on Congressional races, say the recession has left them short of money.

The average House incumbent spent $292,949 in the 21 months ending Sept. 30, up 27 percent from the same period two years earlier. The average for Senate incumbents, which is not comparable to 1989-1990 spending because different states are involved, is $2,351,205.

"We've never had to raise so much money and work so hard," said Representative Thomas J. Downey, a Long Island Democrat who has spent $794,789 seeking his 10th term, "because of the natural vulnerability we all feel." Spending Outpaces New Money

A New York Times computer analysis of reports filed with the election commission showed that incumbents' average spending has risen much faster than their fund raising, and that overall fund raising has risen faster than contributions by political action committees. The incumbents' overall fund raising increased 12 percent, to $363,189, while their contributions from PAC's grew by 7 percent, to $164,575.

Because spending grew faster than receipts, the average incumbent had $153,274 on hand after 21 months, down 16 percent from two years ago.

To avoid distortions caused by an occasional candidate with vast resources, like Michael Huffington, a California Republican who has spent $4,070,908, on a House race, the Times analysis used medians. The median is the point at which half the candidates in a group spent more and half spent less. Mr. Huffington, who is mostly using his own money, is spending more than 174 other major party candidates in open House seats. The median is $175,588.

Candidates in open seats, where neither has the advantages of incumbency, often have the stiffest competition. Democrats held an edge in this category, with the average candidate having raised $225,324 and spent $185,789. Republicans had raised an average of $173,170 and spent $132,188.

The difference was accounted for largely by political action committees. The average Democrat had raised $59,313 from such committees to the typical Republican's $6,850. While the PAC's see no reason to stir up the Democrats -- who control both House of Congress -- by contributing to Republican challengers, they do give to incumbents. The median in money raised from PAC's for a Republican incumbent was $141,385; for Democrats it was $187,850. Hurdle for Challengers

But challengers are generally in dire financial straits. The average challenger has raised only $42,807, with some $1,100 of it from political action committees, spent $34,076 and had $5,397 on hand Oct. 1.

Even so, 31 challengers had raised at least $200,000, the threshold described by Gary Jacobson, a professor of political science at the University of California at San Diego, as "enough to get the message out" and make a race competitive. Twenty of them are Republicans; 11 are Democrats.

Three challengers have actually raised more than the incumbent they are facing. Susan Stokes, a Kentucky Republican, has outraised Representative Ron Mazzoli, by $244,919 to 168,325. But she was aided by the incumbent's unilateral fiscal disarmament; he is among 12 incumbents taking no contributions from PAC's, and he limits individual donations to $100. The legal maximum contribution for an individual is $1,000. Trying to Come Back

The other two House challengers who have outraised incumbents are Gwen Margolis, a Florida Democrat, and Beau Boulter, a Texas Republican seeking to regain the seat he gave up for a Senate attempt in 1988.

Ms. Margolis is challenging Representative Clay Shaw and has outraised him, $573,033 to $430,095. But she had to spend heavily in a primary, and he led her in cash on hand, $419,247 to $110,221.

Mr. Boulter has raised $286,589, to $285,451 for Representative Bill Sarpalius, who got 60 percent of his money, or $170,619, from PAC's. Mr. Boulter got only 2 percent, or $6,735, from them.

In only two Senate races did the challenger raise more money than the incumbent. In California, Dianne Feinstein, the Democrat, had taken in $7,132,821, compared to $6,283,709 for Senator John Seymour. And in North Carolina, Lauch Faircloth, the Republican, had $2,042,555 to Senator Terry Sanford's $1,879,983. The Money Race

Those totals placed them third and fourth among Senate candidates, trailing Representative Barbara Boxer, a California Democrat running for an open seat, who had $8,836,194, and Senator Alfonse M. D'Amato, Republican of New York. Mr. D'Amato reported receipts of $8,154,347.

Ms. Boxer's opponent, Bruce Herschensohn, had raised $5,475,537. Mr. D'Amato's challenger, Attorney General Robert Abrams, had receipts of $5,231,170.

Fifteen Senate candidates, all incumbents, had raise more than $1 million from PAC's, led by Mr. Seymour with $1,274,103. Ms. Feinstein's $696,027 led all challengers. Ms. Boxer's $700,281 led all those in open seats.

Two other Senate races showed close fund-raising duels. Senator John Glenn of Ohio, a Democrat, had outraised his challenger, Lieut. Gov. Mike DeWine, by $2,752,425 to $2,355,665. But Mr. Glenn, who has been raising money for years, had $709,858 on hand and Mr. DeWine had only $56,720.

In New Hampshire, Gov. Judd Gregg, the Republican candidate, had brought in $910,591, to $834,910, for his Democratic opponent in the Senate race, John Rauh. But Mr. Gregg had $177,388 left at the beginning of the month to Mr. Rauh's $22,242.

The median spending by Senate incumbents at this point in 1990 was $1,956,009, much lower than this year, in part because there were no contests in either of the nation's two most populous and expensive states, California and New York. In 1988, the median spending at this point by Senate incumbents was $2,380,568, around this year's level.

None of this year's Senate races will break the Senate spending record of $25.8 million set in 1984 by Senator Jesse Helms of North Carolina and his unsuccessful Democratic challenger, James B. Hunt. Nonetheless, the two Senate contests in California have already produced nearly $27 million in spending in 21 months, just by the four candidates who made it to the general election.