A slight smile crosses Rep. Frank R. Wolf's face when he is asked about his campaign for a sixth term in Virginia's 10th Congressional District.

Overshadowed by the well-financed, headline-grabbing slugfest between fellow Republican Rep. Stan Parris and Alexandria Mayor James P. Moran Jr., Wolf is quietly campaigning against three long-shot challengers in the no-frills fashion that has marked his decade in office.

As usual, Wolf is sticking to the basics and stressing local issues on which even foes acknowledge he has succeeded: transportation improvements, day care and more liberal leave policies for federal workers.

Wolf, who faces Democrat MacKenzie Canter III, independent Barbara S. Minnich and imprisoned political extremist Lyndon H. LaRouche Jr. in the Nov. 6 election, has built a solid political base by responding to constituents' concerns and not making enemies.

He has raised more than $390,000 for the campaign and is such a heavy favorite to win reelection that Canter, who has raised about $50,000, has had some difficulty drumming up support among other Democrats in the affluent district, which includes northern Fairfax, Arlington and Loudoun counties, Falls Church and Fairfax City.

Some political observers say the roots of Canter's problems can be traced to the 1986 election, when Democrat John G. Milliken, then an Arlington County Board member and now Virginia's transportation secretary, raised more than $800,000 in an effort to unseat Wolf.

In what was at that time the state's most expensive congressional race, Wolf raised about $1 million and got 60 percent of the vote. Milliken's defeat had a chilling effect on Democrats in the district, and Wolf was reelected in 1988 by a wide margin.

"The 1986 race was the straw that broke the camel's back," said Francis X. O'Leary, a Democratic activist and Arlington's county treasurer. "There was a feeling that if a Democrat was ever going to beat Frank Wolf, that was the year . . . . This time, Canter's running not only against Wolf, but against the burden of that loss."

Like other Democratic leaders, O'Leary also pointed out a Wolf attribute that has stymied those seeking to unseat him. "He's a nice guy who seems to work hard," O'Leary said. "Wolf's accomplishments are not inspiring, but he hasn't done anything that has engendered any animosity toward him."

Wolf, 51, is a lawyer, former lobbyist and former Interior Department aide who was swept into office during the Reagan landslide in 1980. His reputation as a lawmaker who works behind the scenes with little fanfare was reflected in the dry style with which he ticked off legislative accomplishments at a recent debate in Arlington.

Wolf, of Vienna, noted his role in securing more money for Metro construction, additional car pool lanes on Interstate 66 and several other projects to improve safety on the Capital Beltway. He also mentioned his backing of bills to enable federal workers to donate leave time to fellow employees.

Although Canter, 40, acknowledges Wolf's local successes, he says Wolf lacks vision on national issues and should be held accountable for the soaring federal deficit, the savings and loan crisis and the country's perilous economic situation Canter says are products of Reagan-era policies supported by Wolf.

"Frank's a nice person, but as part of the Reagan crowd his policies have benefited the very wealthy at the expense of the government and the rest of his constituents," said Canter, a lawyer who made an unsuccessful run for the 10th District Democratic nomination two years ago.

Canter said he believes that most of Wolf's constituents "aren't aware of how conservative his voting record really is," and said that if they were, "they'd see the real Frank Wolf in a different light." The Americans for Democratic Action, a liberal scorekeeper, gives Wolf a cumulative rating of 12 out of 100.

Canter played down Wolf's efforts this year to help residents of the South Arlington community of Nauck organize anti-drug patrols. "What he doesn't tell you is that he's voted to cut social programs across the board -- programs like Head Start -- that hit families in that area the hardest," Canter said.

Like Gov. L. Douglas Wilder, who defeated Republican J. Marshall Coleman in the 10th District last November, Canter also hopes to win support for his stance on abortion. Canter supports a woman's right to have one; Wolf is opposed to abortion unless the life of the mother is in danger.

"Everyone agrees with Mr. Wolf on issues of local interest, like transportation," Canter said. "The question is whether his votes on social and economic issues reflect the views of his constituents. I don't think they do."

Minnich, a former federal policy analyst who has no campaign staff and has not received any contributions beyond her own $200 donation, said she is running because voters "deserve something better than the mediocrity they've been getting."

Like Canter, Minnich wants to see higher tax rates for the rich and says Wolf has been invisible on national issues such as the federal budget, civil rights and housing.

"When's the last time Mr. Wolf was a leader on any issue of national importance?" asked Minnich, a homemaker who is operating her campaign from her home in Sterling. "The people of this district deserve someone who will be a statesman, and he's not it."

LaRouche, a former Loudoun County resident, is running his campaign from a federal prison in Minnesota, where he is serving a 15-year sentence for mail fraud, tax evasion and conspiracy in connection with a $25 million fund-raising scheme.

LaRouche, who could not be reached for comment, has raised more than $220,000 for the campaign. He cannot vote because he is a convicted felon, but federal law allows him to run for office and does not require that he live in the district he wants to represent.

He has taken out advertisements on billboards throughout the Washington area, and has purchased time on radio station WTOP-AM in which he criticizes President Bush and several former Reagan administration aides without mentioning Wolf.

Wolf disputes criticism that he is weak on national issues, and defends his support of Reagan economic policies.

"We've cut inflation in half, interest rates are down and we've created thousands and thousands of new jobs," Wolf said. He said Democrats as well as Republicans are to blame for the rising federal deficit, which he said "very well may" require some tax increases and "reasonable spending cuts with equity."

Wolf also refers to his efforts in Romania, where he has gone to press the government on human rights issues, and Sudan, where he went last year to help establish humanitarian aid for hundreds of thousands of starving refugees.

"In 10 years here, I've learned I have the ability to make a difference in people's lives," Wolf said. "Where I see people hurting, I can do something about it . . . . That's what it's all about."