The weakness of the economy has created new fears in the White House of a rout of the Republicans in the congressional elections now just a month away, and Vice President Bush has been told to "toughen up" his campaigning and become "the point man" in a counteroffensive against the Democrats.

But Bush, in an interview during a six-state, cross-country campaign swing that reached its mid-point today in California, expressed puzzlement at talk by presidential aides and Republican National Committee officials of an Oval Office directive to start raising his profile and unloading heavy weapons fire on the Democrats.

"I'm not Spiro Agnew," Bush said. "I'm determined to maintain control of my own campaigning. Sure, you can get more attention if you take the colorful, hatchetman kind of approach, and promise the press some startling prose in every speech. But I'm afraid I'm not that flamboyant."

Reports of the new directive to Bush accompanied a sudden rush of gloomy appraisals from the White House of the risks to Republicans in the Nov. 2 elections. One senior administration official said Thursday that the inroads of the recession and fears of spreading unemployment could cost the Republicans more than 30 seats in the Democratic-controlled House and even endanger enough previously secure Republican senators to put their Senate majority at risk as well.

Those fears put more pressure on Bush, who already is by far the busiest and most visible administration campaigner. The heightened attention to his role was symbolized by the presence on this trip of the top White House political aide, Ed Rollins, and of the scheduled arrival today of presidential speech writer Tony Dolan to bolster Bush's staff.

But the vice president seemed deliberately impervious to the swirling currents around him. "I have no hesitancy to raise my voice," he said. "But I don't see, frankly, that it's more productive than what I've been doing."

What he has been doing -- part-time since last January and almost full-time since Labor Day -- is stumping the country for congressional and gubernatorial candidates in targeted races selected by Rollins in conjunction with Bush's political aide, former Texas state representative Chase Untermeyer, and Bush's scheduler, Jennifer Fitzgerald.

A few old political and personal friends with no particular problems this year have also prevailed on Bush to speak for them. But for the most part, he has gone exactly where the White House has wanted.

His willingness to do so at a demanding pace has drawn praise from many in the party and in the White House. Bush has logged 77,000 miles of domestic travel so far this year, most of it political.

On Monday and Tuesday, in Iowa, Illinois and Missouri, his schedule included 23 events -- speeches, receptions, news conferences and interviews. His staff has compiled a comparison, based on left-over travel documents of former vice president Walter F. Mondale, suggesting that Bush has been a much busier campaigner this year than Mondale was for the Democrats in 1978.

Local Republicans say Bush's campaign staff is competent and courteous. They add, privately, that Bush's people are much easier to work with than Reagan's advance teams. Bush is regarded as a good drawing card, particularly for contributors, and a politician sensitive to the nuances of individual races.

But, as one Republican campaign consultant with close White House ties remarked, "He doesn't light any fires." And, increasingly, Republicans fear they need to do something to avoid being consumed by the burning unemployment issue.

The president is, of course, the Republicans' best campaigner. But he cannot always appear completely partisan at a time of sensitive foreign policy crises. According to some White House officials, there also is an unresolved conflict over his October schedule between those who want him to be more involved in the campaign and those who want to spare him from close identification with what they now regard as an inevitable election defeat.

Of the Cabinet members, only Secretary of the Treasury Donald T. Regan and Secretary of the Interior James G. Watt are regarded as drawing cards, and Watt produces negative reactions from so many people that he has been, in effect, benched.

Leading Republicans in Congress are either preoccupied with their reelection races or pursuing separate campaign schedules, some with 1984 or 1988 presidential ambitions. So the burden of the Reagan administration's campaigning falls on Bush.

Financially, he has been a big success. On this trip, he drew more than $300,000 each at receptions and dinners for California senatorial and gubernatorial candidates Pete Wilson and George Deukmejian. Breakfasts and lunches for House candidates in Missouri and California were five-figure events.

Bush boosted morale, predicting victory for every candidate he met and telling an audience here, "I'm much more optimistic about these races than one should be, just watching the first 30 seconds of the news or reading the headlines" about the economic doldrums.

He tuned his message to the needs of particular Republican candidates. In Cape Girardeau, Mo., where Rep. Bill Emerson is being criticized by the Democrats as a "Reagan robot," Bush said, "Thank God for men with the courage to keep their promises and support the president of the United States."

Here, where Republican nominee Dennis McQuaid outspokenly has criticized some Reagan administration environmental and social policies, Bush said, "We don't want a rubber stamp. We want men of integrity who will vote the way you want."

What he did not do was cuff the Democrats around in a way that would satisfy the wishes of White House aides that he "get on the network news."

His visits are big news in small towns, but in metropolitan areas like San Francisco, the stories and pictures run far back in local papers. His prose almost defies those searching for a headline or a film clip. Bush chose to highlight the importance of the McQuaid race--one of the better Republican chances to capture the seat of a retiring Democrat -- by saying it is necessary to win to "sublimate the obstructionism we encounter" from the Democratic majority in the House.

When Bush went after Speaker Thomas P. (Tip) O'Neill Jr. (D-Mass.), it was with humor, not invective. "I don't want to come down too hard on Tip," he said, laughing. "He's a slow-moving target. You know, we sit up there together when the president speaks to Congress, and I study him. He's really a wonderful fellow. That's the good news. The bad news is he honestly believes that stuff he says."

Bush's basic speech is a bland recital of the favorable economic figures, emphasizing the decline of inflation and interest rates, the reductions in taxes and regulations. He says the choice in 1982 is between new policies that eventually will bring recovery and old Democratic policies that failed in the past.

Even when Bush tries to swat the Democrats, the blow is a light one. In Cape Girardeau, his staff prepared a statement expressing "revulsion" at Democratic National Chairman Charles T. Manatt's comment that Reagan was the "great prevaricator" on his economic record. Bush read the statement decrying these "vicious, low road tactics" as if he were announcing the winner of the door prize, and it made no ripples in the national news.

Seemingly, he could not care less. "I don't know what they mean by 'a high profile,' " he said. "I give a speech in Washington to some group almost every day I'm there, and no one reports it . . . . I want to help us win this election, and if I can do it by making news fine. But I'm really trying to help these candidates, not to come in and overshadow them."

Usually traveling with only one reporter, if any, aboard his plane, Bush was alarmed when several journalists expressed interest in accompanying him last week to Iowa, site of the first presidential caucuses and of his most notable victory over Reagan, a state where he might be thought to be strengthening his political base for 1984 or 1988.

"I'm just not going to look like I'm doing something frantic by way of pushing myself forward," he said, even if that frustrates the White House desire to make him the "point man" for 1982.

He seems determined to remain in character. A San Francisco reporter remarked to Bush that Pete Wilson, a fellow-Yale man, was, like Bush, accused of being "too preppy" in his political style. "I used to hear that," Bush said, "and I got a pretty good job out of it."