Democrats know what they need in new party leader, but can't seem to find him

Democrats grumbled about their outdated image, which seems to have lost its appeal, except to a shrinking number of liberals. But they reelected the liberal and quintessential old-time politician, Rep. Thomas P. (Tip) O'Neill Jr., as Speaker of the House of Representatives.

Next, Senate Democrats groused about their leader, Sen. Robert C. Byrd of West Virginia, who is usually an awkward public spokesman. That was shortly before they overwhelmingly chose him over a challenger, Sen. Lawton Chiles of Florida.

Now the Democratic National Committee is searching for a new chairman to replace Charles Manatt and begin patching back together the tattered Democratic majority. In their longing to woo back the middle class and move beyond the nation's frost belt, some Democratic elected officials have fashioned a concept of the ideal national chairman, with emphasis on ''man,'' since the party has lost favor with male voters.

The want-ad might read: ''Needed: a moderate from a big South or Southwest state; must be an excellent fund-raiser and appealing as a public speaker.''

But as in the other party leadership races, the ''ideal'' newcomer has not appeared. Democratic governors, headed by Gov. Charles S. Robb of Virginia, and other state party officials who met in Kansas City last weekend have called off a search for a ''consensus'' candidate.

Instead, the 377 members of the party's national committee have six announced candidates to choose from, and not one embodies an outreach to moderates and the South. The front-runner is Paul G. Kirk Jr., the party treasurer and a former staff member for Sen. Edward M. Kennedy (D) of Massachusetts.

In fact, all of the candidates have ties to the old party image: Nancy Pelosi , former California party chairwoman, took charge of arrangements for the party's San Francisco convention. Duane Garrett raised funds for Walter F. Mondale. Candidate Robert J. Keefe is a longtime Washington political insider. And former Rep. John Cavanaugh comes from Nebraska, not the Sunbelt. Despite those backgrounds, the winner in the chairmanship race will almost certainly focus on the lost middle-American Democrats. That fact is perhaps clearest in the candidacy of Sharon Pratt Dixon, who cheerfully concedes that she fits almost none of the ''ideal'' criteria. As a black woman from the District of Columbia, the safest Democratic stronghold in the nation, she would appear to represent the shrinking old-line liberal base.

But the self-styled ''corporate conservative'' is breaking the old mold. Mrs. Dixon, a party official, lawyer, and vice-president of the Potomac Electric Power Company, listened with dismay last summer as candidate Mondale promised a tax increase. Her first thought, she says, was that ''I was going to have to pay it.''

''He mentioned the medicine,'' she says of the Mondale tax proposal. ''I wish he'd lingered more on how it would feel'' when the economy ''got well.''

What Democrats must do is regain the image as the party of prosperity, she says, and that will bring in all voters, including the middle classes. ''Everybody wants to be successful,'' she says, and President Reagan offered more hope for prosperity than the Democrats. The party overemphasized the Equal Rights Amendment and ''affirmative action'' to assist minorities and women, Mrs. Dixon says. The ''first order'' of business is to restore US competitiveness in industry, and the answer is a business-government-labor partnership, which the Democrats would be best suited to forge, she says.

Her fellow candidates have echoed a call for a new Democratic vision. In less specific terms, Mr. Kirk has urged his party to ''reclaim'' its heritage as the ''party of ideas'' and to build bridges to the South and Southwest.

''I understand the traditional Eastern and Midwestern base,'' he says. ''I also recognize that it's not enough'' to win national elections. Kirk has also declared his ''independence'' from his former boss, Senator Kennedy.

Former Mondale campaign vice-chairman Garrett has likewise put distance between himself and Mondale. ''We didn't reach out to young voters, the mainstream, the middle class,'' he says of the '84 election. He repeats a criticism leveled at candidate Mondale - that the party must ''stop viewing society as a collection of groups.''