Amid the partisian rhetoric and cries of outrage yesterday about President Reagan goring the poor came a telling remark from a seasoned political pro from Austin, Tex. "Reagan used the right analogy," said Bob Armstrong, a longtime state official. "If you're going in one lane and you're not getting anywhere in one lane, it's time to switch lanes. I'm glad to see him try."

If Armstrong were a Republican, his remarks could be dismissed as just another political volley. But he is a lifelong Democrat, Texas land commissioner and Jimmy Carter loyalist to the bitter end.

What Armstrong's remarks reflect is a widespread feeling that Reagan and his Democratic opponents are acutely aware of as they enter the battle over Reagan's program. Simply put, there is a broad consensus in the country that there is a need to "switch lanes" -- to do something different.

Individuals differ sharply in their reactions to the details of the president's economic plan but they are sympathetic to its general thrust -- as long as it hits everyone equally. "I have mixed emotions about the cuts," said Bill Paetzold, a third-generation farmer in Hereford, Tex., who has participated in American Agriculture Movement protests in Washington. "But we've got to straighten this mess out. I don't know if he's right or wrong, but I'm going to stand behind him until it's proved he's wrong."

That process started in earnest yesterday. The people with oxen being gored by Reagan's proposed budget cuts did just what they were expected to do. They began screaming.

They spoke in many accents, and in behalf of many concerns dear to their hearts. But their message was pretty much the same. Listen to a few of their voices.

William Wells, county judge of Floyd County, Ky., in the heart of Appalachia: "Anytime you're taking food out of the mouths of children, i'm against it. We don't think food stamps or welfare are abused in our part of the country. I can't see how it's going to help the economy by putting people out of work. As for tax cuts, they won't benefit my people."

Mary Weisenberger, a sophomore at the University of Michigan: "Most of my aid comes from the government. If Reagan cuts my loans I probably won't be able to to to school here anymore. I'd like to finish, but i might not be able to."

Steve Young, an unemployed auto worker from Kokomo, Ind.: "If they do what Reagan wants to do to unemployment compensation, I'll lose my house, I'll lose my car. My wife is pregnant. Thank God my Blue Cross is still good, but I don't know how I'd feed the baby because I couldn't get food stamps."

These were reactions from people who would be directly affected by Reagan's economic proposals. The reaction from Establishment America was predictable. Republicans and businessmen generally supported Reagan; Democrats and special-interest groups that would be hit by the proposed cuts questioned the plan.

The language from both sides was full of battlefield bravado. The signal was clear: another classic left-right confrontation was under way over who has the best interests of "the people" -- particularly the disadvantaged -- at heart.

Two all-but-forgotten figures from the past, both speaking before Ohio audiences, provided a certain symmetry to the decades-old debate.

First, from Columbus, came former president Richard M. Nixon, speaking before a political forum for the first time since resigning the presidency in 1974. Reagan's message to Congress, he told a sold-out audience, is "the most important economic speech given by an American president since World War II."

Then, from Athens, Ohio, came the words of Arthur Schlesinger Jr., an old liberal warhorse, warning everyone to be prepared to see Reagan's "free market theories fail." Supply-side economics, he declared, is simply another form of "the trickle-down theory . . . the theory that if the rich get rich enough, then some of it will trickle down to the rest of us."

The words sounded like an old family argument had simply been renewed. To be sure, many of the players were in their familiar roles. "The president's program is a high-risk gamble with the future of America," the AFL-CIO said in a policy statement from Bal Harbour, Fla. "Workers and the poor take the lion's share of risk. The only sure winners are the wealthy."

United Mine Workers President Sam Church threatened to call a national strike to protest a proposal that would make it more difficult for miners to get black-lung benefits. Thomas A. Shannon, executive director of the National School Board Association, said the proposed budget cuts amounted to "a declaration of war against public education."

Willie Brown, speaker of the California General Assembly, said Reagan "clearly has an aversion to the arts, or to public-assisted arts. . . . He's always had something against welfare." Atlanta Mayor Maynard Jackson, like many other bit-city mayors, said he was worried. The proposed cuts "will have a severe impact on the city of Atlanta. . . . Let us understand there will be many more people out of jobs . . . that the poor will be poorer and the working poor will be worse off."

There was, however, a certain tentativeness and qualification to many of the remarks. Jackson reflected this as well as anyone when he said "our parents taught us to live within our means; so must our nation."

This was tacit acknowledgement that the nation's political equation has changed, as has the old debate over who gets what. Reagan is going into the debate in unusually strong political shape -- and his opponents are well aware of it.

A survey for Newsweek last week by the George Gallup organization found that 48 percent of those polled think more favorably of the new president now than they did on Election Day. The poll showed that Reagan has strong support for cutting government spending, which 32 percent of the respondents blamed for the high rate of inflation. It also found that he has broad support for cutting the food stamp program, subsidies to the Postal Service and public jobs programs.

Both Democrats and Republicans sounded uneasy in their new roles. "We conservatives are a lot like the dog who has been chasing the car wheel," said Rep. Mickey Edwards (R-Okla.) "We've finally caught it and now have to figure out what to do with it."

The first word from the political right was that Reagan had proven himself a true conservative. Four groups claiming to represent "the mainstream of the conservative movement called an early news conference here yesterday to announce they were going to do all they could to support the president.

One group, Citizens for Reagan, said it will mail 2 million letters in support of the proposed budget cuts. The Fund for a Conservative Majority said it would raise $4 million to defeat congressional candidates who oppose the economic plan.

Reagan's message to Congress was "the beginning of what comes close to a political revolution in this country," said Edwards, chairman of the American Conservative Union. Proposing the economic package was a courageous political act, he said, an "equitable example of cost cutting" that would raise cries of outrage only from selfish special-interest groups. "Everyone whose ox has been gored is going to be squealing," he said.

This is where the rub comes. Many groups and individuals think the proposed budget and tax cuts simply are not fair.

"Everyone in the arts is willing to sacrifice," said David Kent, general manager of the Kansas City Philharmonic Orchestra, which depends on help from the National Endowment for the Arts. "We're willing to bite the bullet, but the depth and scope is not in keeping with what other areas of the budget are being asked to give up. Under the defense budget, the military spend $52 million in 1980 on military bands. The National Endowment for the Arts' entire budget for music programs last year was only $13.5 million."

The scope of the proposed budget cuts in such that the state of Georgia, for example, would lose about $562 million, including $70 million in Medicaid payments, $52 million in school aid, $100 million for public jobs under the Comprehensive Employment and Training Act program, and $109 million in aid to local governments.

Many people feel torn over the economic package. "We, as much as the president, want to increase the nation's productivity and restore economic stability," said Ruben Bonilla, head of Texas' League of United Latin American Citizens. "But the question arises: At what expense and whose greatest sacrifice?"