CHESTERTOWN - Rep. Wayne T. Gilchrest is in his element. Dressed in a short-sleeved white shirt and loosened tie, he's ambling alongside a parched cornfield, talking drought, nutrient management and land preservation with a clutch of farmers.

If Gilchrest had his way, he would replay this recent appearance on a Kent County research farm again and again, campaigning for a seventh term in Congress by fervently rattling off the minutiae of environmental policy that has become his political trademark.

Not this time.

Twelve years after he surprised pundits in both political parties with a low-tech, everyman pitch, and a decade after his folksy style prevailed over the glamour and celebrity of former basketball star Tom McMillan, Gilchrest is running hard.

Gilchrest, a self-described moderate Republican, faces a Sept. 10 primary challenge from David W. Fischer, a Baltimore County lawyer and a fervent conservative who says he believes he can outflank Gilchrest on the right, attacking his "environmental radicalism."

"He calls himself a moderate, but I think his voting record is very liberal," Fischer says. "Gilchrest was more likely to vote with Bill Clinton than any other Republican member of Congress."

Conservative coalition

According to the most recent Federal Elections Commission report, Fischer has pumped $113,000 of his own money into his first bid for office and has garnered support - and a pledge for $100,000 or more in campaign contributions - from the Club for Growth, a conservative group that champions property rights, lower taxes and privatizing Social Security. The National Rifle Association is also backing Fischer.

A political unknown who grew up in Kentucky, Fischer, 32, has drawn the ire of party regulars for taking on an incumbent.

The 6-foot-6-inch former small college academic All-America basketball player was sharply rebuked by Paul D. Ellington, the Maryland GOP's executive director, for a series of ads Fisher has been running in local newspapers throughout the district.

The advertisements say a "safe Republican district deserves a congressman who actually votes like a Republican." Among other charges, the ads accuse Gilchrest of siding with the "liberal Clinton Administration on issues like gun control, abortion, gay adoption, flag burning and private property rights."

"If you want to invoke the name of Ronald Reagan, then follow Reagan's 11th Commandment - never speak ill of another Republican," Ellington said. "Wayne can't be described as an ideologue. He's very practical-minded. I don't see David Fischer as the arbiter of who is and isn't a real Republican."

Also running for the seat are Republican Brad McLanahan of Annapolis, who has challenged Gilchrest before, and Democrat Ann D. Tamlyn of Centreville.

Gilchrest, 56, expects to raise $200,000 for the primary. He is stumping "seven days a week," especially in the northern portions of the district, where once-a-decade redistricting by the state's ruling Democrats shifted 160,000 people from Harford and Baltimore counties into the 1st District. The district also includes 100,000 Anne Arundel County residents and nearly 400,000 people in Gilchrest's nine-county Eastern Shore home base.

A green record

Gilchrest, a former civics teacher who served as a Marine Corps platoon leader in Vietnam, has made environmental issues his focus, tirelessly pushing for greater Chesapeake Bay protections and farmland preservation.

He says recent polls show he has very high name recognition, even in new portions of the district. Supporters say his record on the environment will play well with voters in urban areas where development is an issue.

Last spring, Gilchrest won a provision in a farm bill to create a conservation corridor, a network of farmland, woods and wetlands he says will help keep the Delmarva peninsula one of the last green places on the East Coast.

Two years ago, Gilchrest won kudos from environmentalists, but antagonized Baltimore business leaders, Gov. Parris N. Glendening and the Army Corps of Engineers by opposing state port officials' plan to dump dredge spoil from bay shipping channels at a site near the Bay Bridge. Some still see the successful fight against open bay dumping as a blow to Maryland's business interests.

Hitting back

Stung by what Gilchrest says are distortions of his record - charges by Fischer that he supports gay adoptions, is a threat to private property rights and supports banning hundreds of types of firearms - Gilchrest has hit back, characterizing Fischer as a fringe candidate who is out of step with most voters.

"I think he's appealing to a very narrow group of Republicans," Gilchrest says. "There's some kind of mythical concept, some kind of mythical dogma, of what a Republican is supposed to be. I've voted with George Bush something like 86 percent of the time."

Stephen Moore, president of the Club for Growth, which helped elect 10 conservative candidates to Congress two years ago, sees Gilchrest as a vulnerable target and Fischer as worthy new foot soldier to carry the conservative banner.

"The way you beat an incumbent is by lining up all the conservative groups, and that appears to be happening," Moore says. "When you're running against an incumbent, it's always about the incumbent. This is a referendum vote on Wayne Gilchrest."

Fischer reacted angrily to criticism from the Gilchrest camp that he seized the spotlight last month by representing a family whose children were abused by a Kent Island karate instructor. Fischer's call for opening the court records of juvenile sex offenders who are charged with similar crimes as adults generated a flurry of publicity, including appearances on two cable television news programs.

Gilchrest supporters say the stance conflicts with Fischer's work in several cases as a defense attorney, cases in which he sought reduced sentences for sex offenders.

"I've done nothing to hide the fact that I'm a defense attorney and have represented a wide range of people," Fischer says. "I made every effort to avoid exploiting the families in the Kent Island case. This is just attack tactics."

Picking up support

Lately, Fischer, who has been running ads on WBAL Radio in Baltimore, has been picking up support from anti-abortion conservatives, winning tacit approval from several General Assembly members from Harford and northern Baltimore counties who remain reluctant to ruffle party unity by officially endorsing his candidacy. Gilchrest, they say, is out of sync with many conservative suburbanites.

In a Republican primary that most predict will draw no more than 30,000 GOP voters to the polls, Fischer supporters are gaining confidence that he could win with 17,000 or fewer votes.

"This kind of thing happens sometimes to people who've been in office for a long time - they wander from their core issues," says state Sen. Andrew P. Harris, a Baltimore County conservative Republican who sympathizes with Fisher's stance against gun control and abortion. "If Wayne didn't see this coming, he should have."

Personal connection

Gilchrest insists that Fischer and others underestimate the connection he has made with voters and the credibility he has earned over the past 12 years. His supporters say they value Gilchrest's independence and reputation as a free thinker.

"There are a lot of green Republicans out there, many who secretly admire a politician who speaks his mind," says Hugh Smith, a GOP insider who owns an Easton real estate firm.

"This constituency here on the Shore responds to personal contact and affinity, not mass marketing," Smith says. "Down here, people know if they need something from Wayne, they just call him at home."