Peter Espada, a General Accounting Office economist and an Arlington Republican, said that his political career began five months ago with a telephone call from Rep. Frank R. Wolf (R-Va.).

"He called me up and said: 'Please run, we really need your help,' " said Espada, folding his hands as if in prayer and looking toward the ceiling. "Sure, John Milliken looks invincible," the congressman told Espada, "but we think you can do it."

With that, Espada, 33, was launched on what he concedes has been the uphill battle of trying to unseat John G. Milliken, the vice chairman of the Arlington County Board and one of Northern Virginia's most prominent Democrats. It was a task that almost every GOP activist in Arlington had been offered, and which none wanted.

"I know there are a lot of doubters out there who say, 'Oh, he can't win,' " said Espada, who is running as an independent with a Republican endorsement.

He said his goals in Tuesday's election are not only to pull off an upset, but to get back at the Democrats who he says have treated him patronizingly. "I'm a proud person by nature. My family name is at stake."

Espada and about five close friends have done almost all his campaign work, from drafting campaign literature, picking up leaflets from the printers and slipping them under doors -- all on a budget of about $23,000.

They're up against an experienced Democratic organization that commands hundreds of volunteers and which has raised $42,000.

They're also up against Milliken, 39, who is the chairman of the Metro Board and a tax lawyer with Walter F. Mondale's Washington firm.

Espada has tried to portray Milliken as a clone of Mondale, a wild-spending liberal and a captive of special interests.

The race has featured a clash of styles between the steady, articulate, lawyerly Milliken and the peppery Espada.

Milliken, who is seeking his second four-year term on the five-member board, has expressed puzzlement about how to deal with what he calls Espada's frequently inaccurate or misleading allegations.

"I've been a little upset by the inaccuracies," Milliken said. "But I don't want to do a George Bush on him."

Earlier this week, Espada -- in a departure from the frequently subdued ways of Arlington politics -- alleged that the county's new equal employment opportunity policies, which were supported by Milliken, will force the county government to recruit homosexual workers.

Espada says that those "radical" policies will expose schoolchildren to "weird concepts when they're very young."

Milliken says that Espada is wrong in charging the county will have to recruit homosexuals.

The employment policy simply states that the county cannot discriminate against prospective employes on the basis of "sexual orientation," and does not force the county to recruit homosexuals, he said.

Further, the policy applies only to county government job and not to school jobs, the Democrat said.

Espada said he got the idea to attack Milliken on the issue from a group of Arlington women. The group has mailed more than 500 leaflets to county voters endorsing Espada and charging Milliken is "pro-homosexual."

Democrats have been upset over other Espada charges.

One of his flyers castigated the County Board for approving a homeless men's temporary shelter in a residential neighborhood, and implied that Milliken voted for it.

Actually, he voted against it. Asked about this, Espada said Milliken "tried to rob me of the issue. How could he vote contrary to his Democratic brethren?"

Another Espada flyer criticized Milliken and the board for increasing the density of a planned office and shopping mall complex at Pentagon City beyond a limit set by the board in 1976. The board, however, has not increased density at the project beyond the old limit.

Asked about this, Espada said: "I don't remember the details. . . . I'll be glad when this campaign is over."

An Espada letter to voters charged that Milliken opposes cutting taxes, even though Milliken last spring voted to lower the county tax rate by 2 cents, to the current 97 cents per $100 assessed value, the area's lowest tax rate.

Espada also frequently attacks Metro as an out of control bureaucracy, and suggests Milliken is partly responsible.

Espada acknowledged in an interview that Milliken has a reputation for trying to control the transit systems' costs, especially on small-budget items.

"I think it's easy to complain about lightbulbs," Espada said. Asked for specific mistakes Milliken has made on the Metro board, Espada could not provide any.

"John's maintained a very low profile," he said.

When Milliken follows Espada in addressing civic associations, he often starts his remarks with a gentle admonition such as, "I think what Peter meant to say was. . . . "

Espada said he becomes enraged by Milliken's "patronizing" attitude in correcting him, and by County Board Chairman Ellen M. Bozman's "very arrogant" manner.

He said one of his main goals is getting back at these people who he feels patronize him.

"I guess it's just the Latin temperament in me," he said. "My campaign manager has had to physically restrain me."

Espada's campaign has sought to capitalize on his Hispanic background by distributing Spanish-language leaflets in Hispanic neighborhoods. But he said the campaign has been stretched too thin to target Hispanics in particular. Espada's father is Puerto Rican and his mother was Italian-American.

Milliken, once an aide to former congressman Joseph L. Fisher of Arlington, reminds voters about his record, which he said includes votes that have controlled development around Metro stations, allotted more funds for schools and provided services needed by Arlington's changing population.

Increasing numbers of elderly residents in the county should prompt the county to provide more recreational facilities and home day care for them, Milliken said.

The rising population of single-parent families will mean more daycare facilities, he said, and the county must respond by regulating them closely.