As Democrats gathered to elect the first black chairman of a major political party, they were told Wednesday to find presidential candidates who are "able to speak to the South" as well as to white Protestant voters.

Pollster Peter Hart pointed out to the party's executive committee that in the 1988 presidential election, Republican George Bush won 155 electoral votes in the South compared to zero for Democrat Michael Dukakis."You can't start out any game behind 155 to 0 and be competitive," Hart said. He also said that 48 percent of all voters are white Protestants: "We have to be able to talk to them," he said.

In the 1988 campaign, Hart said the Republicans ran on values such as anti-crime and pro-defense while the Democrats ran on programs. "We've got to be able to get from programs to values," he added.

After two days of preliminary sessions, the Democratic National Committee will convene on Friday to select Ronald H. Brown as the next party chairman.

Brown, a former aide to Sen. Edward M. Kennedy and Jesse Jackson, is unopposed for the top party job. But his impending election was raising questions about the help or harm it might bring, particularly in the South.

"Will it help?" asked Atlanta-based pollster Claibourne Darden. "The answer is no. What can Ron Brown do to help the Democratic Party? Bring the liberal vote to it? It's already there.

"Bring the black vote to it? It's already there."

Merle Black, professor of political science at the University of North Carolina, said Republicans would use Brown's election to put out the message to Southern whites that "the Democratic Party now is the party of blacks."

Still another analyst of Southern politics, Larry Sabato, of the University of Virginia, said Brown's election could cause problems for Democrats in the region "not so much because he's black, but that he's tied to the twin devils, Ted Kennedy and Jesse Jackson."

Among the Democrats, two new studies were circulating of political trends in the region that was once the party' most reliable base.

One looked at 1988 presidential election returns in seven Southern states and disclosed that Republican George Bush consistently beat Democrat Michael Dukakis in the region's fastest-growing and most affluent counties.

Bush swept the Deep South on Nov. 8. Dukakis' best showing was in Louisiana where he trailed with 45 percent of the vote. He received 40 percent or less in Alabama, Florida, Georgia, Mississippi, South Carolina, and Virginia.

The second study focused on Alabama and urged the state Democratic Party there to "turn its attention toward gaining a greater understanding of why it has failed to capture significant support within Alabama's white voting population."

Written by pollster and DNC member Natalie Davis, the study concluded that in Alabama "the Democratic Party has been a no-growth party."

Concern over the party's dwindling appeal among white voters in the South became an issue in the campaign for party chairmen. However, Brown overcame four rivals in the contest to succeed Paul G. Kirk Jr.

With the exception of 1976, when Georgian Jimmy Carter was the Democratic presidential nominee, Republicans have carried the South in recent national elections.

In its study of 1988 election returns in seven Southern states, the Institute for Southern Studies found that the counties carried by Bush were "richer, whiter and growing nearly twice as fast as the counties carried by Dukakis."

In addition, the analysis determined that Bush was strongest in areas with the highest voter turnout. "The numbers show that the Democratic ticket in November just didn't excite voters the way the Republican ticket did," said Bob Hall, research director of the institute.