Some of Prince George's County's highest-ranking elected officials -- including County Executive Parris Glendening -- endorsed Baltimore Mayor William Donald Schaefer's campaign for governor yesterday.

A list of more than 50 supporters released by the Schaefer campaign at a picnic promoting State's Attorney Arthur A. Marshall's reelection effort included the names of six of the county's eight state senators and 10 of its 23 delegates.

Last month, three dozen officeholders and candidates for state and county offices gathered in Prince George's County to endorse Schaefer's opponent, Attorney General Stephen H. Sachs.

Such division among the county's elected officials over the gubernatorial nomination has resulted in a significant split in a county that usually has presented a unified front engineered by the dominant Democratic organization.

"Certainly Prince George's County has people who have not made their minds up," said Schaefer's Prince George's cochairman Winfield Kelly Jr. "It's not my job to coerce anybody."

Schaefer's name will appear at the top of many of the sample ballots that are handed out on election day but, Kelly said, "there won't be a consensus countywide."

Schaefer, who toured the county yesterday, predicted that he would win in Prince George's. He said he would overcome Sachs' slight lead in the polls in the Washington area, and the disarray among black Schaefer supporters that occurred when U.S. Rep. Parren J. Mitchell Jr., who is black, joined Sachs' ticket.

Glendening has been an ally of Schaefer on issues before the Maryland General Assembly. Although those warm relations turned slightly frosty when he was host of a meeting last year between Schaefer and a group of highly critical black leaders, Glendening said it was natural for him to endorse the mayor.

"I've worked with him on issues that were mutual problems," Glendening said. "I like Steve Sachs, but I've known the mayor and worked with him."

Schaefer said he hoped to benefit from Glendening's evident popularity in Prince George's. Of the earlier rift between the two, Schaefer said: "It's over. Over."

"Today was the best day I've ever had in the county," said Schaefer, who met hostilty on one of his earliest forays to Prince George's last year. "Endorsements are great, but on the other side of the day I spent a great deal of time meeting with plain people."

Sachs was also in Prince George's yesterday touring the University of Maryland's Science and Technology Center with Bowie Mayor Richard Logue. The facility, he said, "shifts the center of gravity in the state" to make the Baltimore-Washington corridor "the new crossroads of Maryland."

Sachs also praised the latest surge of economic development, saying that the county now has a "a vibrancy unparalleled in the state."

Sachs got his biggest show of support from Logue, who found a four-leaf clover in the grass while the two men were touring. "I'm good at things like this," Logue said. He handed the clover to Sachs, who responded: "This is the day we won."