In California, where Jesse Jackson has built his strongest campaign organization, the Jackson camp is geared up for the long haul to the June 5 state primary, which closes the primary season.
This sets up Walter Mondale - who has proven to be Mr. Jackson's chief rival for the nation's black vote - for a long, tough fight.
''It'll be bare knuckles all the way,'' says John Floyd, Jackson's cheerful, suspender-clad state campaign coordinator.
If it is a scrappy fight for ethnic voters here, how damaging will the long scrap be to Democrats?
Mr. Floyd says the Mondale campaign is already playing hardball politics in jawboning Jackson backers, often using Mr. Mondale's close ties to the Democratic Party structure.
Michael Kantor, state chairman of the Mondale campaign, is more conciliatory in tone. ''It will be a tough fight in the (black) community and a fair fight,'' he says. But the vigor that Jackson injects into the campaign, he adds, is ''wonderful for the Democratic Party'' and ''the best thing that could happen to Walter Mondale.''
Yet Jesse Jackson clearly hurts Walter Mondale, just as Mondale clearly cuts into Jackson's black support.
Blacks, Hispanics, and other ethnic minorities comprise nearly a quarter of the registered Democrats in California, according to the Field Institute, an independent public-opinion analyst. And the Jackson camp is still pushing a voter-registration drive here.
Gary Hart figures less prominently in this battle. While California's independent-minded and youthful Democrats have a profile that bodes well for Hart, the Colorado senator has not shown any strength among ethnic minorities.
No polls of California attitudes have been released here since the recent primaries in the South and Illinois, where both Mondale and Jackson have made strong showings, so it is not clear exactly how the two candidates stand with voters here. At this point the battle is an organizational one:
The Jackson people are working from the bottom, trying to clear a path to power for their populist candidate with grass-roots support; the Mondale camp is working from the top to secure its claim to the support of opinion leaders in the ethnic communities.
Jackson can arguably claim to have the most democratic campaign here. Earlier this month, the Jackson campaign held caucuses in all 45 of California's congressional districts - the only campaign to do so, Floyd points out.
He cites the ethnic makeup of these caucuses in support of Jackson's claim to a ''rainbow coalition.'' Of more than 8,000 people who attended Jackson caucuses , half were black, 28 percent were white, 14 percent were Hispanic, and 7 percent were Asian-Pacific.
Further, says Floyd, each of three Jackson caucuses held in mostly black Los Angeles districts drew about 1,500 people, more than any caucus held in the 1980 presidential race.
Mondale, on the other hand, has fared better with endorsements. ''We have some very impressive and popular leaders in the Mondale camp,'' notes Mr. Kantor. The list includes Los Angeles Mayor Tom Bradley, Oakland Mayor Lionel Wilson, Congressman Mervyn Dymally, and Assemblywoman Teresa Hughes.
Kantor feels Mondale is running strong with Hispanics as well, citing congressmen Edward R. Roybal and Mathew Martinez, both of the East side of Los Angeles, state Sen. Art Torres, and Assemblywoman Gloria Molina, among others, as Mondale backers.
''The Asian community,'' Kantor admits, ''is still up for grabs.''
Larry L. Berg, director of the Institute for Politics and Government at the University of Southern California and a longtime campaign consultant for Democrats, is concerned the Jackson-Mondale battle will be divisive for the party.
The battle puts black leadership in an awkward position, according to Dr. Berg. The politicians who support Mondale risk losing their support among black voters, especially if the Jackson campaign continues to gain strength and enthusiasm. Politicians who support Jackson risk losing their clout in the Democratic Party.
Assembly Speaker Willie Brown Jr., one of the state's most powerful black politicians, supported Alan Cranston's bid and has remained uncommitted since Senator Cranston dropped out.
Mayor Bradley was an early and steadfast Mondale supporter, but most politicians agree that Bradley draws so much of his support outside the black community, and it is so tied to his performance in office, that he is not vulnerable on this front.
Maury Weiner, deputy state campaign manager for Jackson, is a veteran leader in all of Bradley's mayoral campaigns. He sees the current battle in the Democratic contest the way Mondale campaigners like to see it, as a struggle that will only deepen the party's commitment to beat Ronald Reagan.
''I think it will be relatively easy, the way this campaign has been conducted so far, for any of the candidates to support the nominee,'' says Mr. Weiner.