Presidential hopeful Sen. Bob Dole (R-Kan.) used Campaign America, a group ostensibly formed to promote the fortunes of Republican candidates around the country, to pay for eight trips to New Hampshire, the first presidential primary state, last year.

Presidential hopeful Ronald Reagan used a similar group, Citizens for the Republic, to build up a mailing list of more than 300,000 contributors and maintain a network of political operatives for much of the year.

Presidential hopeful George Bush used another such group, Fund for Limited Government, to pay for $40,203 in air travel last fall while he tested the political waters.

There's apparently nothing illegal about any of these activities. But they illustrate how a new breed of "political action committees" has become the latest wrinkle in presidential politics.

With hardly anyone noticing and no real criticism, the committees mushroomed into a major force in American politics last fall with some of their number controlling budgets that rival traditional special interest lobbies.

Reagan CFTR budget of $2.5 million, for instance, was larger than that of the political arms of the AFL-CIO, the American Medical Association, the antigun-control lobby, or the United Auto Worker union last fall, according to Federal Election Commission reports.

Technically, the Doyle, Reagan and Bush groups -- and similar organizations keeping alive the presidential hopes of John B. Connally and Gerald R. Ford -- were formed to aid Republican efforts across the nation.

There's little doubt they did just that. But whether that was their main purpose is another matter.

The pledge cards for Dole's group, for instance, said, "Yes, I'm interested in helping Campaign America support Republican candidates across the country."

Yet less than 6 percent of the $202,000 the Dole group raised went directly to candidates. And 11 percent of the $230,000 the Bush group raised went to candidates.

The rest went for travel and overhead. The amounts were considerable: Of the $2.5 million Citizens for the Republic spent last year, $1.9 million went for operation expenses; of the $632,812 raised by the John Connally Citizens Forum, $498,309 went for operating expenses.

This money enabled former California governor Reagan to visit 86 cities in 26 states last year, and former Texas governor Connally to visit 167 cities in 40 states.

The benefits were obvious. At each stop they could lay claim to be helping Republican office seekers and face a platoon of reporters asking their favorite question -- "Are you going to run for president in 1980?"

Connally's name recognition moved up 17 points in the Gallup Poll during the 15 months his committee was in operation; Reagan, who was much better known at the start, moved up 6 points in the same period.

The candidate political action committees are a creation of federal election law revision, and, at least in part, were set up to circumvent the law. "The law is a bad law. It's a terrible law," says Lyn Nofziger, chairman of Reagan's CFTR. "But it's there, and as long as you have laws you're going to have people figuring out how to get around them."

The committees skirt the law in two ways:

They avoid contribution limits. Individuals are normally limited to giving $1,000 to a candidate. But they can give $5,000 to a "multicandidate political action committee."

They enable a presidential hopeful to raise and spend money without it counting against the maximum spending limits -- which are expected to be about $14 million in 1980. The limits apply to every candidate who takes federal matching funds, which most are expected to do.

The main advantage of the candidate political action committees is that they allow presidential hopefuls to do what presidential hopefuls have always done without breaking the law.

"They look like presidential campaign committees, they act like them, but they aren't," says Herbert Alexander, one of the nations best known experts on election financing. "They're deceptive. But all the candidates need them if they're going to test the political waters. There's really no other way to do it."

The political operatives who run the committees insist their primary purpose is to help other candidates. Last fall, the groups provided a new source of financing for Republican candidates, pumping $752,403 into Senate, House and various state campaigns. The presidential hopefuls also attracted media attention and raised hundreds of thousands of additional dollars by serving as the featured attraction at fund-raising events.

No one, however, pretends it's a one-way street. "I think these committees are very beneficial to the candidates. If, on one hand, Bob Dole receives some benefit for helping others, well, that's the way politics work," said Paul Russo, executive director of Campaign America. "Everyone knows he's very interested in 1980."

"When a guy like George Bush or John Connally helps Republican candidates, he's helping himself," said Jim Baker, chairman of the Fund for Limited Government. "They're doing what Richard Nixon did in 1966, collecting chits by going around the country."

Reagan's CFTR is the first, largest and most successful candidate committee. It was also the one that contributed the most to other candidates -- $553,490, or more than the political committees set up by General Motors, U.S. Steel, Union Oil, or General Electric executives.

CFTR got its start in 1977 using $1 million left over from Reagan's unsuccessful 1976 campaign. "This was not formed as a subterfuge to move Ronald Reagan around the country," says executive director Nofziger. "In fact, when we formed this I was confident that Reagan would not be a candidate in 1980."

But more than any of the other groups, CFTR has functioned as a shadow presidential committee for Reagan -- complete with advance men, fund-raisers, political advisers and accountants. It has fine-tuned a mailing list of 300,000 proven Reagan contributors and provided lucrative employment for a skeleton campaign staff.

Nofziger, a longtime political adviser to Reagan, heads a full-time staff of 26. He receives $4,000 a month. A firm headed by two other longtime Reagan assistants, Mike Deaver and Pete Hannaford, received $61,833 in CFTR consulting fees last fall.

John Laxalt, brother of Sen. Paul Laxalt (R-Nev.), Reagan's 1976 national chairman, is on CFTR's Washington payroll at $3,000 a month. John Sears, Reagan's chief political strategist in 1976, has received CFTR legal fees.

"It will be interesting to see how long Reagan continues to warehouse these people on the CFTR payroll," says the chairman of a rival group who asked not to be identified."The Federal Election Commission ought to look at this and look at it closely."

CFTR, apparently alone among the groups, plans to continue in operation after the 1980 election.Bush's Fund for Limited Government has closed, and Connally's forum is about to.

"The election is over. We've done what we set out to do," says Baker, chairman of the Bush group. "Unlike most of the other groups, we didn't want a big fancy organization or staff competing with the Republican National Committee."