No pothole is too small for Joseph Alexander.

For 20 years the Fairfax County supervisor has made a profession of finding and filling potholes and resolving the thousands of mundane problems that vex life in suburbia. When residents of Spring Drive complained recently that parked cars were blocking their street, Alexander got not one but 30 "No Parking" signs installed in a two-block area.

His Lee District has managed to snare $12 million to $15 million in drainage projects, which is probably more, officials say, than any district in the county. Its parks have grown from 114 acres to 2,200 acres, a remarkable accomplishment for what is a largely developed area.

Alexander's ability to funnel millions of dollars into his district, a chunk of Fairfax containing 74,279 residents around Springfield Mall, has helped make him the marathon man of elected local officials in the Washington area. No supervisor, councilman, or county board member in the region has managed to outlast the Democratic supervisor's two decades in the same job.

How Alexander, a short, round-faced, 53-year-old savings and loan executive whose father was once a lieutenant in Virginia's Byrd organization, has survived two decades of social and political change is, some say, a testimonal to political savvy.

To many, the reason is simple: Alexander is a "pothole politican," who has proved that residents of suburban tract housing are as fond of back-slapping, pork-barrelling politicians as are city residents.

"Joe has Lee District so well organized, almost like a Chicago ward," said Democrat Jean Packard, chairman of the 1970s slow-growth Board of Supervisors with which Alexander often clashed.

"When Joe's constituents have a problem, he has a problem," said Fairfax lawyer and developer John T. (Til) Hazel. "Most people talk about the district as Joe's District . . . instead of Lee District."

Mention that Alexander's critics call him a "pothole pol," and the supervisor, who has cared for his district the way a parent would fret over an only child, will snap back: "Hey, I'm proud of that name. That's what we're supposed to do. In my opinion, unless we're taking a vote on something like the budget or taxes, we don't accomplish much of anything at those board meetings. Yes, we can make resolutions and argue amongst ourselves.

"But this," he says, motioning toward a massive drainage ditch he got built in his district, "is where the action is."

Among his eight colleagues in Fairfax, Alexander is courtly and polite. But at times he has seemed abrasive and short-tempered as a member of the larger Metro transit board where he has long represented Northern Virginia. Still his mark is there: The extension of the Yellow line toward the Franconia neighborhood where he used to run a hardware store is labeled the "J/H" on Metro charts, a designation planners jokingly refer to as "Joe's hardware."

His critics complain that Alexander is overly concerned with Metro. Republican Thomas J. O'Connor, who is expected to be Alexander's opponent this November, charges the supervisor has been in office "too long," and spends too much time with the Metro and national transportation matters, to the detriment of his district.

On the surface Alexander is an unlikely model for the consummate political survivor. The only child of rural Franconia's only Jewish family, Alexander dreamed of being an aviator, not a politician. His easy-going manner and his polyester suits seem more appropriate for the hardware store owner and fireman that he once was. He's the guy next door, says one Democrat, somebody you'd want to go golfing with.

The casualness, others say, is deceiving. "His good ol' boy veneer that he has in his district is completely blown away when he's at a Metro board meeting," said Jim Kornick, a former aide and now executive director of a redevelopment agency created at Alexander's urging to help rehabilitate the aging Rte. 1 corridor. "You see him in his plaid polyester jacket at the fire station and then you see him in his pin-striped suit at Metro or the bank."

Alexander is vice president of the Perpetual American Federal Savings and Loan Association, where he supervises the development of savings accounts and plays troubleshooter when the savings and loan has trouble with neighboring governments.

Critics have charged that Alexander faces conflict-of-interest problems whenever a developer who has borrowed money from Perpetual, comes before the board. Alexander says he disqualifies himself in such cases.

"It's easy to underestimate him at first. He's not a thinker of new, revolutionary ideas," says Kornick. "But when he sees a problem, he fixes it."

Sure enough, Alexander keeps detailed files on matters such as potholes and traffic problems, and when the county agrees to fix the problem, he or a staffer often accompanies state or county workers to the sites to explain what needs to be done. Once the work is completed, his staffers make follow-up checks.

In his spare Saturdays and Sundays or between meetings, Alexander drives around checking potholes and other items, "just to make sure."

His initial exposure to politics came from a pro, his father, Milton, who was a Fairfax County justice of the peace and an active member of the Byrd machine. Milton Alexander's annual crab feasts were for years a celebrated fall ritual among Virginia Democrats. The father, now Fairfax's chief magistrate, and son now jointly sponsor the gatherings, an indication of the ease with which the younger Alexander bridges the gap between the Byrd machine and the new suburban Democrats.

Many of those who turn out for the feasts are the supervisor's longtime followers, individuals who more often than not have been his appointees to numerous county commissions, boards and task forces. They serve as Alexander's eyes and ears in the Lee District. The core of that group is not the local Democratic Party, with whom Alexander is sometimes at odds because of his close ties to business and his prodevelopment stance, but the Lee District Association of Civic Organizations.

"There is a firm coalition of people who support Alexander," says Democrat Packard. "Party labels don't mean anything. The support is really apolitical; it's a loyalty to an individual or maybe to a family."

Alexander prides himself on knowing the Fairfax bureacracy, and often bypasses public meetings for behind-the-scenes manuevering. "Joe got to know everybody on the county staff," says former Supervisor Virginia McEnearney, who represented the adjoining Springfield District in the early 1970s. "And when he wants something done, I mean really wants it done, he doesn't wait until a board meeting to ask the county executive to look into it."

By the time the matter reaches the board, "Joe has already spent several hours with county staff and has started things rolling," she said.

While most supervisors prefer to gamble that a controversial project will not attract public attention, Alexander often is on the telephone with district residents as soon as he is hit with one, such as the drug rehabilitation center the county placed in his district. It always is better if residents hear about a controversial project directly from him, he says.

"His style is more that of the down-home, old-style politics," said one county Democrat. "People don't think that works in the suburbs any more, yet he's managed to do it his way."

To some politicans who have left the county board for higher offices, Alexander's part-time $20,759-a-year job may seem mundane. Not Alexander. "The only exotic issue that I deal with on a regular basis is transit and that's exotic enough for me," he says. "I'm just a home-grown local individual that likes to work with my constituents, and that's it.

"I don't have any illusions for any of the higher issues or more complicated, sophisticated issues. I feel that my mission in life is solving problems for the citizens and accomplishing something tangible. And I feel that in local government you can do that."

During the county board's recent redistricting, Alexander was incredulous when another Democratic supervisor balked at having a largely Republican area with severe drainage problems placed in his district. "That's not a problem," he exploded. "That's an opportunity."