In Virginia's diverse 20th District - Loudoun and Prince William Counties - three incumbent Democrat are seeking renomination for second terms in the best of all possible political worlds. They have no opponents.

When Floyd C. Bagley, Earl E. Bell and David G. Brickley have to start campaigning this August, "It will be the 'Three Bs' running together as a ticket in both counties," according to Bell.

Bell is a Leesburg auto dealer who lives near tiny, Quaker-settled Hamilton in the lush, rural northern tip of the district.

Bagley, from Dumfries, and Brickley, from Woodbridge, live in the southern tip along the Interstate Rte. 95 corridor of rapid residential growth which has changed the character of Prince William County.

Despite the sharp differences in their counties, the three men frequently refer to themselves as the "three Bs," agree on most major issues and view themselves as a distinct part of the Northern Virginia delegation. Floyd Cladwell Bagley

Bagley, 55, was born in Maine and came to Virginia at 17 to become at Marine. He rose to master sergeant and received a battlefield commission as a second lieutenant in 1944. He returned to enlisted ranks after World War II, and was again commissioned as an officer during the Korean War. Bagley went to law school while still a Marine and retired as a captain in 1959.

He ran unsuccessfully for the House of Delegates in 1961 and 1969, for the U.S. House in 1964 and for Commonwealth Attorney in 1967. He went back on active duty in 1970-71 as a Marine Corps military judge and became Prince William County Attorney in 1972, a post he held until his successful 1975 race for the House of Delegates.

Bagley said he believes no tax increase will be necessary next session if the state bond issue passes. If a tax increase proves necessary, he would favor a one per cent hike in the sales tax.

He said the present system of choosing judges by party caucus should be changed. An independent panel not dominated by lawyers should make the initial recommendation, according to Bagley. He favors state purchase of Freestone Point as a park and says that the state's counties and cities should be able to agree on an annexation procedure acceptable to both.

Bagley said new sources of revenue for local jurisdictions would be a major issue for him in the next assembly, as would legislation to provide incentives to industry. He strongly favors a tax on tobacco and says legislators are so underpaid that only the well-to-do can afford to serve. He favors higher compensation and an extender session. Earl Edward Bell

Bell, 56, owns the Chrysler-Plymouth dealership in Leesburg, has been in the auto business for 27 years and has lived near Hamilton for nine years.

He had never run for office before 1975 when "the Democratic committee was looking for a candidate and put a little pressure on."

"I thought maybe I could do some good for my county and the state," said Bell. "I learned you can't change it overnight."

Bell said his major concern now is to make operation of the state government more efficient. He said the state can avoid a general tax increase if the bond issue passes.He would raise taxes on "items that are not a necessity - tobacco, booze, possibly cosmetics" if money were needed locally to take pressure off real estate taxes.

Bell said that during the past session, for the first time, 20th District delegates attended all Northern Virginia caucuses. "Some of the issues, like Metro, don't affect us directly, but we have gone along with the delegation," he said.

He said he was not in favor of changing the procedure for selecting judges because of the high quality of judges in Loudoun County. Bell said he favored no-fault insurance two years ago but now has doubts based on problems encountered in states with no-fault laws.

Disclosure rules should be more rigorous and the equal rights amendment and parimutuel betting should be approved in the state, he said.

Bell said Democrats in the 20th had intentionally balanced their ticket with one candidate from Loudoun and two from Prince William and that the differences in the areas did not came a problem because "we work together." He said he was strongly opposed to anything that takes power from local governments.

David G. Brickley

Brickley, 33, came to Virginia as an Air Force intelligence officer in 1970, left the service in 1972 and was assistant county executive in Prince William County in 1974-75. He now manages an investment company in Falls Church.

A major effort has gone into making sure Northern Virginia gets its share, but the region should still be getting more of a return on the taxes it pays to Richmond, Brickley said.

He said he had about a 50 per cent average on legislation in the past session, getting through a bill that allows localities to refinance debts at lower interest rates, a "pay as you go" bill that requires one free toilet in public places and adding paid firemen, police and rescue workers to protection from law suits under the Good Samaritan law.

Brickley said the state can provide necessary services without a tax increase next year. He also called for passage of a local option cigarette tax, election of school board members, parimutuel betting and the equal rights amendment.

He said he favors stronger disclosure legislation, with high state officials being required to reveal their source of income. Brickley also said he supports collective bargaining with public employees with a particular eye toward a strong no-strike provision, and favors state action on making Freestone Point a park.

Brickley said the General Assembly should reconvene after its session in order to override vetoes and make technical corrections in legislation.

In Richmond, where Brickley, Bell and Bagley occupied side-by-side rear row seats in the House chamber, they were known as the "the three B's" during their freshman terms.

Of the three, it was the New York-born Brickley who spokemost often on the House floor. His style, which some delegates viewed as brusque and imperious, once got him into potentially serious trouble.

During a debate on an obscenity bill he was backing, Brickley accused Rep. Clinton Miller (R-Shenandoah), an opponent of the bill, of saying things on the floor that he wouldn't say "back home."

That brought a murmur of discontent, and Brickley later made a public apology to the full House. Under House rules, delegates are not allowed to attack each other personally.

Bell and Bagley assumed the more conventional role of freshmen legislators, rarely speaking on the floor.

Auto dealer Bell raised some eyebrows when he vote on a bill that favored auto dealers. He said in an interview that he had planned not to vote on the bill, but had decided to do so because he grew tired of seeing lawyers in the Assembly vote on "lawyer bills" and bank directors vote on "bank bills."