Political action committees are the dominant source of congressional campaign funds.

Corporate PACs are the fastest growing of the ilk.

Republicans take in more PAC money than Democrats.

PACs have weakened the parties.

PACs have driven a wedge between legislator and constituent.

PACs have enabled business interests to capture Congress.

In capsule, that's the popular wisdom on PACs. It's also dead wrong on every count.

So contends the Public Affairs Council, an organization of Washington-based corporate executives that is launching the first public relations counteroffensive on behalf of the ubiquitous and oft-maligned PACs, which raise money from employes, union members and issues activists and distribute it to candidates.

Richard A. Armstrong, president of the council, has raised $100,000 so far from his group's 425 corporate members (about half of whom have PACs) to commission monographs, films and research to rebut the "disinformation" he says he believes is rampant.

"I tried the idea out last summer on my members and there wasn't a great deal of interest," he said. "But we had a spate of negative stories during the 1982 election, and now there's a big push for public financing. We need to get our side out."

From Armstrong's point of view, the public relations campaign is starting just in the nick of time. Today a bipartisan group of 50 members of Congress will introduce new legislation to place a limit of $90,000 on the amount that any House candidate can receive from all PACs in any two-year election period.

A similar bill passed the House three years ago but died in the Senate. Its chief sponsor, Rep. David R. Obey (D-Wis.), said the new version has been strengthened by providing for an overall spending ceiling of $200,000 on House general election races.

It also would provide for a voluntary partial public financing system in House races and would create financial incentives for candidates to abide by the PAC and spending limits. The incentives would include extra public financing for the opponents of candidates who ignore the limits.

"We do not pretend that this proposal will equally handicap each candidate for Congress like a horse race," said Obey. "We don't know anyone who's smart enough to do that. What we are trying to do is equalize as much as possible the legislative playing field so that the legislative process is not warped by the combined effect of organized political contributions."

Armstrong said he believes that Obey, his reformer friends in Congress and a large swath of an "unquestioning" press have been captured on the issue by Common Cause, the self-styled citizens' lobby that has been pushing public financing for the past 12 years.

He contends that Common Cause generated the negative publicity about PACs in the first place, and now is using it as proof there is some sort of popular groundswell against them.

"It's wonderful to find out one has such extraordinary skill and ability," Fred Wertheimer, president of Common Cause, said of the charge. "But he totally misses the point of what is going on. In earlier years you did not have members of Congress speaking out about PACs the way they are now. Clearly there is a new recognition of the fundamental problems PACs are causing the system."

The first product of the council's campaign, a paper by Dr. Herbert E. Alexander, a political science professor at the University of Southern California and a leading expert in the field of campaign finance, is being circulated in Washington. It lists, and seeks to rebut, a number of "myths" about PACs:

* Myth: PACs nationalize campaigns and divorce officeholders from their constituents.

Despite their dramatic growth in the past decade, Alexander notes, PACs still play a modest role in congressional election financing--accounting for 29 percent of the funds contributed to House general election candidates in 1980 and 21 percent of the funds to Senate general election candidates. In that same year, he writes, individual contributions accounted for 67 percent of the funds to House candidates, 78 percent of the funds to the Senate candidates.

Alexander argues that some "nationalization" of fund-raising is both inevitable and desirable, as congressmen must consider national interests as well as local ones.

* Myth: The sharp growth in corporate and other business-related PACs is tilting the fund-raising scales heavily toward Republicans.

Actually, Alexander notes, PACs have consistently favored Democrats over Republicans, and 1982 was no exception. Democrats got 56 percent of all PAC money in 1978, 52 percent in 1980, and through Oct. 13 of last year, they got 56 percent.

There are several reasons for this. Business PACs have always been more bipartisan in their giving patterns than labor and they tend to tilt heavily toward incumbents, regardless of party affiliation. Morever, in 1982, the biggest percentage growth in contributions was among labor PACs, which gave $20.4 million, compared to $13.2 million two years earlier. As usual, labor gave 94 cents out of every dollar to Democrats.

* Myth: PACs have contributed to the decline of the political parties.

Alexander argues that the decline of parties was well under way by the time the PACs came onto the scene in the mid-1970s, in part to fill a void created by the parties' failures. He also notes that the revival of the fund-raising capability of the Republican Party over the past decade demonstrates there is room for parties and PACs side-by-side.

* Myth: Like-minded business PACs exert undue influence on legislative decisions.

Alexander argues that business is no monolith; that what is good for one industry is often bad for another. He also argues that the tables served up by Common Cause and other watchdog groups demonstrating the correlations between PAC contributions and the votes of members of Congress are a narrow, anecdotal view of the public policy process that arbitrarily assigns weight to a single factor.

The receptivity of Congress to business interests in the first two years of the Reagan administration, he says, was not a result of PAC power but of the perceived mandate of the 1980 elections. The 1982 elections, Alexander argues, changed that perception and business interests will do less well as a result.

Armstrong said he plans to flesh out that last point by commissioning a separate study to demonstrate instances of "negative correlations" between campaign contributions and votes.

He also said he plans to commission a study to show there is a "good-government" case to be made for PACs. His hypothesis is that people who give to PACs are more inclined to vote and to get involved in the political process.

"It's like a horse race," he said. "If you've got a couple of bucks down, it's something more interesting than a bunch of four-legged animals running around in a circle."

As Armstrong sees it, a public financing bill may pass the House this year but is unlikely to survive the Senate. He says he sees the real showdown coming in 1985, and the thrust of his effort will not only to defend PACs but to focus attention on the myriad of complications in any proposed scheme of public financing for congressional campaigns.

Wertheimer, meanwhile, decribes his campaign as a "Riggo drill for Redskins fullback John Riggins . . . , a couple of yards at a time, plugging away at the abuses of the system."

The public, according to recent surveys, is sympathetic to both arguments. In a December study by the Roper Organization, respondents, when told that PACs were "committees formed by coporations, labor unions, trade associations and other groups to raise money that is then donated to political parties or candidates," said that they were a "bad thing" rather than a "good thing" by 43 to 21 percent.

However, support for public financing of congressional campaigns has waned over the years. Last November the Harris Survey found 53 percent of his respondents were against the idea; in 1975, following Watergate, just 37 percent were opposed. And a Civic Service Inc. study last year, posing the public financing question in a way that did not emphasize the spending limits implied, found the public opposed to the idea, 61 percent to 28 percent