In the wake of Tuesday's upset of Montgomery County Executive Sidney Kramer, county workers and officials began yesterday to ponder what until now had seemed implausible: Neal Potter at the top.

They are used to Potter on the inside, worrying about the details of each county undertaking. And they know of Potter on the outside, frequently the lone questioner on a council he often criticized as too compliant.

Now, with the 20-year council veteran favored to win the Nov. 6 general election, attention turned to the prospect of Potter, the leader. More specifically, a host of county decisions and projects appear to be, if not threatened, at least subject to further review:

The proposed light-rail trolley between Silver Spring and Bethesda, which Potter questioned and now believes should be studied more.

Plans for a massive trash-to-energy incinerator bitterly opposed by residents of the rural northern part of the county.

The controversial office-and-shopping redevelopment of downtown Silver Spring that sparked opposition to Kramer.

The county's plan to build a new jail in Clarksburg, which is opposed by State's Attorney Andrew Sonner, a Potter supporter.

The recently adopted plan for the area called Shady Grove, which has been criticized by civic activists as allowing too much growth.

These are the issues that many believe brought out anti-Kramer voters from all parts of the county in a relatively low turnout of county Democrats. Potter won all the county's legislative districts except one.

"There have been changes before . . . but I don't think I can ever remember one where an incumbent was ousted or where there was such a change in philosophy," said one department head, including the change in the 1970s from Republican James Gleason's administration to the Democratic regime of Charles W. Gilchrist.

"The civic activists in my area this morning are absolutely elated," said Barnesville Mayor Elizabeth Tolbert, who said Potter's victory is widely seen as a possible reprieve for the part of the county set to get both the incinerator and a landfill.

Potter's ability to implement policy could be enhanced by the council elected in November. Expanded this year from seven to nine members, the council could include as many as five Democrats endorsed by Potter and two Republicans who share some of his slow-growth views. Potter actively campaigned against incumbents Rose Crenca and Michael Gudis, both of whom appeared to be defeated Tuesday. Final results in Crenca's race won't be known until absentee ballots are counted today.

Potter tried yesterday to reassure the news media and the public that he doesn't believe in "change for change's sake." He said he would not call for wholesale resignations if he is elected, and that his administration would not be a revolution.

"I'm not in a big hurry to make a lot of changes," Potter said. "First, I have to get by another election and . . . second, it's not my nature."

Potter is seen by Democratic and Republican activists as a solid favorite in heavily Democratic Montgomery over GOP nominee Albert Ceccone, a real estate investor from Chevy Chase.

Ceccone, who has run unsuccessfully for Congress and who lost his party's primary for executive four years ago, said he intends to hit Potter with the same issues Potter used to topple Kramer: taxes and development.

"We are going to have a race," Ceccone said.

Kramer had touted his relationship with Gov. William Donald Schaefer during the campaign, and the executive had the solid support of the county's business and development community. Both Schaefer and county business leaders put the best face on yesterday's results and said they are optimistic that they could work with Potter.

"People in Montgomery County made the decision on Sid and Neal Potter," said Schaefer, who contributed $7,500 to Kramer and campaigned in the county on his behalf. "I think it was an indication that growth is on the people's minds."

Schaefer said he expects policy changes in Montgomery County and added, "I would want to know relatively soon his position on light rail." The state has pledged $70 million toward the trolley project.

Some members of the county's business and development community -- who said they were unfairly buffeted by the debate over growth that dominated the race -- expressed concern.

"We don't really know what it means. He seems antigrowth and antibusiness, so you have to worry," said a salesman for a commercial real estate company.

Other business leaders offered congratulations, and said past problems would remain in the past.

"We are looking forward to as good a working relationship with the next county executive as we have enjoyed with Mr. Kramer," said Laura Warshauer, president of the Gaithersburg and Upper Montgomery County Chamber of Commerce.

The shock of Potter's primary victory and the possibility of changes in county policies and personnel caused widespread anxiety throughout the county's full-time work force of 6,400 employees.

"There is not a whole lot of work being done today," said one worker in the Executive Office Building in Rockville. Only the 29 members of Kramer's cabinet are without civil service protection, but employees said that a change at the top could affect their daily work lives.

Tim Firestine, a county budget chief, said, "You expect some stability and then all of a sudden -- boom, there is change."

Staff writers Veronica T. Jennings and Howard Schneider contributed to this report.