IN THE United States between 1976 and 1978, prices overall increased by around 15 percent. During that same period, some prices went up considerably faster than the average. For example, the cost of running for, let alone winning, a seat in the House of Representatives went up 44 percent. lPreliminary figures from 1980 indicate that the growth in campaign costs is continuing.

Because most congressional seats are safely in control of one of the two major parties, most are not closely contested. Still, in 1978, Democratic and Republican candidates for the House managed to spend an average of $108,000 per contest. But the real spending story is in the financial reports from the 74 congressional districts in which the winner received 55 percent of the popular vote or less. In those close House races, the candidates spent an average of $448,000. That is serious spending just about anywhere, the kind of serious spending that depends on serious fund-raising.

In the last couple of elections, such fund-raising has meant that more and more candidates have sought and received contributions from political action committees, or PACs -- especially from corporate PACs, which have managed to grow even faster than the inflation rate. Six years ago, there were 89 corporate PACs. This year, there are 1,153 registered with the Federal Election Commission.

That kind of growth has enabled PACs of all kinds to play an even bigger role in House elections. For the average congressional candidate in 1972, PAC contributions made up 14 percent of total contributions. By 1976, that PAC share had grown to 22 percent and by 1978 to 25 percent. All during this period, the campaign costs were growing much faster than inflation. So the PACs were growing even faster than those campaign costs, which was nothing short of phenomenal.

In case anyone thinks that only the House candidates have been increasing their spending or their reliance on PAC-giving, it should be pointed out that, between 1974 and 1978, the cost of an average Senate compaign increased from $455,515 to almost $1 million.

Last year, the House did what is always most difficult for incumbent officeholders to do: it imposed restrictions on its own ability to raise campaign funds. The House, after vigorous debate, adopted the proposal of Reps. David Obey (D-Wis.) and Tom Railsback (R-Ill.) to limit House candidates to $70,000 in PAC contributions per election, with a ceiling of $6,000 from any one PAC in the primary and general election combined. Currently, candidates have no such limits in overall contributions from PACs and can accept, in one primary and general election campaign, up to $10,000 from any one PAC.

Senate Republicans threatened a filibuster even though the Obey-Railsback rule would not have affected senators at all, only House candidates. And PAC giving has been heavily tilted, usually by a margin of 3 to 1 or better, to incumbents over challengers. So the House's action must be viewed as a serious response to a serious situation.

The Obey-Railsback amendment still represents an important chance to curb the growing clout of political action committees. The time is very short. Senate Republicans should rise above narrow partisanship and support the House limit on PAC power in Congress. Now.