Most of President Carter's political initiatives during his first 100 days in office were suggested in a previously unpublicized 51-page memorandum written in December by Patrick H. Caddell, Carter's political pollster.

Caddell urged Carter to exploit "symbolic" devices like reducing the number of White House limousines and appearing often on fireside chats and in other, less-conventional, public forums. He proposed a new presidential image that is "bold, imaginative and skeptical - in short, 'refreshing.'"

Caddell's "Initial Working Paper on Political Strategy," made available to The Washington Post yesterday, predicted that Carter's most serious political opposition would come from Democrats - particularly from Gov. Edmund G. (Jerry) Brown Jr. of California, "who must be viewed as the single largest threat on the horizon within the Democratic Party," according to the memo.

Caddell also said Sen. Edward M. Kennedy (D-Mass.) had begun - in December - to express private reservations about Carter, and the pollster warned that a group of "young Turks," including Sens. Gary W. Hart (D-Colo.), Joe Biden Jr. (D-Del.) and Dick Clark (D-Iowa) and Gov. John D. Rockefeller IV of West Virginia, "may want to exercise their right to challenge [Carter] quickly . . . if not handled properly."

Caddell said Carter should use the Democratic National Committee to identify "and hopefully coopt the people who might help staff opposing political campaigns."

"One of the best ways . . . to limit the potential opposition in the future," Caddell wrote, "is to remove from the job market as many of those with the experience and talent in presidential politics as can be accommodated."

Carter has adopted many of Caddell's recommendations, going well beyond the symbolic gestures the pollster suggested. Caddell also proposed a dramatic energy policy, support for postcard registration and other policies to encourage voter turnout, early action on behalf of welfare reform and government reorganization, a new style of presidential rhetoric which is more candid about the complexity of public issues, and measures to make the DNC "a political arms of the Carter White House."

Carter has also declined to act on many of Caddell's suggestions. For example, the pollster proposed that Carter personally and publicly deal with a few citizens' complaints about their treatment by government agencies. He also suggested ordering government regulators to spend some time working in the industries they regulate, and he recommended early symbolic action to demonstrate concern about crime.

Writing early December, when Carter was beginning to announce appointments to his Cabinet. Caddell argued strongly that the new President should chose new faces for his administration. "Jimmy Carter has given the American people a commitment to bring new, fresh blood to Washington," Caddell said. "For his own success, it is vital that that commitment be kept."

Caddell noted that there was "already . . . skepticism" in the press and public about this commitment.

At 26, Caddel was the youngest member of Carter's inner circle during last year's presidential campaign. He became an influential adviser, according to Carter's associates, by making tactical and policy recommendations based on the results of his public opinion polls.

According to Hamilton Jordan, Carter's principal political lieutenant, Caddell was one of five or six persons Carter asked to write memos after November's election. "There was no same plan per se." Jordan said, but rather a variety of ideas proposed by Carter associates.

"Now I'm not discrediting Pat's memo" Jordan said in a telephone interview, "but I think several of us called for fireside chats, open government, things like that."

Caddell said in a separate telephone interview that his memo was "just my views." He said he wanted to offer "some long-term thoughts . . . and suggestions" to Carter. His most important idea, Caddell said, was that the best politics is the best government."

"I'm not ashamed of it at all," he said.

In the memo Caddell wrote that, in his view, "governing with public approval requires a continuing political campaign." He also predicted that "the time is ripe for political realignment in America - for the construction of a political coalition based on a successful Carter administration."

Old labels and the old coalition that made up the traditional Democratic Party are now obsolete, Caddell argued. He identified the decline of party strength and membership as the crucial fact of modern political life - and as the basis of Carter's new political opportunities.

"What we require is not [WORD ILLEGIBLE] composed of bits and pieces of old policies," Caddell wrote, "but a fundamentally new ideology . . . We desperately need an ideological 'paradigm' toreplace the 'free market capitalist model' that we don't really want . . . American society . . . needs some kind of direction."

Caddell attributed the accomplishments of "our most successful primary opponent, Jerry Brown" to the fact that "he was able to present an ideology that fitted no tradition in a rhetorial style that was refreshing to voters."

Caddell said there was no longer great significance to the labels "liberal" and "conservative," and he suggested that Carter could appeal to people who regard themselves as both. He called it a failure of the campaign that so few conservatives voted for Carter in November.

Caddell gave short shrift to the traditional opposition, the Republican Party. It "seems bent on self destruction," he wrote. "We have an opportunity to adopt many of their (the Republicans') issue positions and to take away large chunks of their normal presidential coalition." Caddell wrote. "Unfortunately, it is those same actions that are likely to cause rumblings from the left of the Democratic Party."

Traditional elements of the Democratic Party, Caddell wrote, might prove to be opponents of the new administration. Besides Brown and the "Young Tunks," he identified other potential opponents:

Labor organizations and big city political machines, traditional bastions of Catholics and ethnics, according to Caddell. However, he wrote, these should be "the easiest for Carter to dominate" because "they have party loyalties that go back for many years and a willingness to accept any status [WORD ILLEGIBLE] that provides them with power and patronage."

"The liberal establishment" which, Caddell wrote, is "in many ways as antiquated and anachronistic a group as are the conservative Republicans," but which has "far greater weight than their numbers" because of "representation in the establishment, the media and in politics."

Liberals like Kennedy, Sen. George McGovern (D-S.D.) and Rep. Morris K. Udall (D-Ariz.), wrote Caddell, see "little risk in challenging an incumbent President" and feel an "overwhelming desire to do so."

Congress, "Carter's quick rise from relative obscurity to the White House," Caddell said, "is by its very nature a direct threat to the style and experience of the men who make up the leadership of the Congress. While they intend to cooperate, they are anxious to be independent."

Congress is also the setting for one of four "immediate political problems" Caddell outlined in his memo. "The Korean CIA investigation (of congressmen alleged to have taken bribes from the Korean government) may embarrass many Democratic congressmen. We can't go on the defensive; anti-Washington and ethics rhetoric must be ready."

The other immediate problems Caddell cited were the "slow" economy; the need to persuade "our budget people" to spend "what we have well, rather than thinking up new ways to spend"; and the need to counter any attempt by Gerald Ford to paint his successor as a "big spending liberal."

Caddell urged Carter not to shy away from matters of style. "Too many good people have been defeated because they tried to substitute substance for style," he wrote. "They forgot to give the public the kind of visible signals that it needs to understand what is happening."

He listed half a dozen "stylistic points" which he said should be emphasized - "with their substantive counterparts": Carter "as an open man," Carter as "different from other politicians," Carter as someone who "is not part of the establishment" (something which "must . . . be reflected in his appointments"), the administration as compassionate, competent, non-ideological and responsive to ordinary people.

Caddell urged Carter to develop new themes for his administration - themes intended to build trust in the new President, so the public would wait for him to fulfill his major promises. "The Carter administration . . . desperately needs to buy time," Caddell wrote because most of Carter's major policy proposals "will require two or three years to implement."

His list of "themes" included: healing the country, restoring trust in government, giving a sense of purpose, "a new ideology," and "new working relationships" - the appearance of better cooperation within government, between business and labor, and so forth.

Another way to achieve the impression of progress and accomplishment, Caddell wrote, would be to set and attain some modest goals early on. "It is crucial that Carter obtain a series of easy early victories that give the sense of promise for the longer term," Caddell wrote. "Use early victories as signals that the entire issue program will succeed."

Caddell's memo included specific proposals for actions Carter could take at the time of his inauguration, in the first week, and in the first few months. For example, at the time of the inaugural he suggested "making symbolic gestures in terms of personal style . . . perhaps by ostentatious use of guests such at Bob Dylan. Martin Luther King Sr. and perhaps an older conservative to make some points."

In the first week, Caddell proposed: "Zero-based [TEXT OMITTED FROM SOURCE]

"Zero-based budgeting announced to departments as something to begin thinking about.

Further symbolic gestures (cutting down limos for the brass, 'sunshine' orders).

"Abolition of at least some of the 1,200 boards and agencies.

"The pardon proclamation [amnesty for draft violators].

"Submission of the 'reorganization' authorization legislation to Congress."

Among Caddell's proposals for "the first few months" were the following:

"Perhaps an attack on 'big steel' for its recent misbehavior.

"An effort to end some unneeded regulation (Civil Aeronautics Board, Interstate Commerce Commission).

"An energy policy - perhaps in the context of forming the unified energy agency that has been promised.

"The first town meeting - perhaps in the West or Middle West.

"President visits departments.

"A fireside chat on government reorganization.

"Weekly announcements of 'waste rooted out . . .'

"A concentrated reorganization assault on one agency or program."

Caddell concluded his memo with a warning: ". . . It is vital that we got off to a quick and successful beginning. Carter needs to gain personal credibility and restore the trust of the people. If he can do this, he may convince them to give him a chance . . . to solve some of the long-term problems . . . If we don't buy the time quickly, given their mood today, the American people may turn on us before we ever get off the mark."