ANNAPOLIS -- When Theodore J. Sophocleus began thinking about running for Anne Arundel County executive two years ago, one of the first things he did was head south. As a County Council member from Linthicum, a working-class suburb of Baltimore, he needed to know how his folksy brand of politics would play with the boating crowd and well-heeled rural landowners closer to Annapolis.

Sophocleus was mindful that "north county" politicians historically had suffered the farther from home they strayed. With 52 percent of Anne Arundel's increasingly affluent electorate living in the southern and central portions of the county, failure to do well in the south could prove fatal to his ambitions.

"The thing you have to show in your political life is that you haven't been a north county guy, that you understand about farmland preservation, that you understand about water quality and that you haven't tried to undermine the people who care about those things," said Sophocleus, who faces a south county politician, Republican Robert R. Neall, in the Nov. 6 general election.

Encouraging conversations with civic leaders and other groups outside his district convinced Sophocleus, 51, that he could make significant inroads into the south. But the Democratic nominee's concern illustrates the lingering political and sociological split that has existed between the areas of the county that are oriented to Baltimore and those that are closer to Washington.

Outgoing County Executive James Lighthizer, a product of the south county, said he found it difficult to be accepted in the north and so will Neall. "There is a definite bias by many north county voters against non-north county politicians," Lighthizer said. "There was a feeling that I was a guy in a suit, an outsider."

North county residents -- many of them descendants of immigrants who moved to the county in the 1940s -- tend to be blue-collar and die-hard Democratic. Union halls, volunteer fire stations and the remains of the old Democratic clubs make areas in the north among Arundel's most politically active.

To the south are the waterfront communities, traditional middle- and upper-middle-class suburbs of single-family homes that were developed as homesteads for lawyers and business executives. Along with the horse and tobacco farms south of Annapolis, where family roots date back centuries, these areas comprise a strong core of Republicans and conservative Democrats.

Annapolis, with a population that is 35 percent black, traditionally has voted Democratic, although the neighborhoods that ring the city are more inclined to cross over. The wild cards are the fast-growing areas to the west that border Prince George's and Howard counties, housing an eclectic mix of working-class, middle-income and conservative voters.

The north-south rivalry dates to the 1950s, when a Democratic-controlled political machine in the north dominated the county board of commissioners. More recently, north county residents have complained that they are shortchanged in the distribution of money for parks and schools.

Although some observers interpret Sophocleus's victory in the Democratic primary, in which he swept every councilmanic district but Annapolis, as a sign that the north-south divisions are over, others believe the geographic rift will still play a role in his race against Neall.

Neall, 42, represented a large chunk of the south and central county for 12 years in the state House of Delegates, where he gained a reputation as one of the legislature's leading budget analysts.

"Ted Sophocleus is a professional, he is a pharmacist. Having said that, the people down here will vote for Bob Neall," predicted Circuit Judge Warren Duckett, an Annapolis resident. "They consider themselves more like Bob Neall than Ted, who unless you talk to him in person and see how educated and likable he is, can still come off from a distance as a north county politician."

Analysts who share Duckett's outlook point to the 1982 Democratic primary for county executive. In that race, Lighthizer, a south county state legislator, narrowly captured the nomination when his two north county rivals split their base. Lighthizer went on to defeat the Republican candidate, an Annapolis alderman.

With the National Security Agency and a military defense division of Westinghouse as its largest employers, the county has tended to be more conservative than Prince George's and Montgomery counties. Although Democrats outnumber Republicans 1.5 to 1 and used to enjoy a far greater advantage, two of the county's three executives have been Republicans and none of them has been from the north.

Mark Anderson, who was Lighthizer's campaign manager in 1982 and is now advising Sophocleus, says the county's growth during the 1980s has made the voters less predictable. As more young professionals have moved into the north county, bringing with them no sense of having been ignored in Annapolis, the county seat, the old biases have been diluted, he said.

For that reason, Anderson said, geography is likely to be less of a critical factor in the election than income. Although neither candidate has tailored his message to a particular area, Sophocleus's pledge that he would be a compassionate, community-focused leader is likely to play better with blue-collar voters. Similarly, Neall's contention that his history as a fiscal conservative makes him the better choice in an uncertain economic climate will probably appeal more to business groups and property owners.

"I don't see an issue that would not appeal equally to north and south. They are appealing to different interests by selling themselves," Anderson said.

Nevertheless, with a little more than three weeks remaining until the election, most analysts, including Anderson, are expecting Sophocleus to win the three northern councilmanic districts and Neall to win the three southern districts. The race will be decided on who wins the seventh, western district and how strong a showing they make in each other's areas, analysts say.

Neither Neall nor Sophocleus subscribe to this scenario. Neall, for instance, notes that Republican voter registration has increased 22 percent in the county since 1986. What's more, many of the former die-hard Democrats voted for George Bush for president and for Neall when he ran for Congress four years ago.

"No one has said to me, 'You are from south county and are hereby disqualified,' " Neall said. "I just don't think it's as much of a factor as it used to be."

Sophocleus, meanwhile, says that the sizable Greek community in Annapolis and the support he is receiving from organized recreation groups, environmentalists, senior citizens and public employee unions -- advocates whose influence extends countywide -- will help him overcome Neall's advantage in the south.

"Sometimes the person who drives the BMW doesn't want to elect someone who drives a BMW and the person who drives a Chevy doesn't want someone who drives a Chevy," he said. "I give them more credit than voting for someone who is just like them."