A week after former Colorado senator Gary Hart's presidential campaign was the target of adverse publicity about questionable financial aid to his current and 1984 campaigns, additional allegations have been made, and the chief federal prosecutor in Los Angeles has asked the FBI to investigate.

The Orange County (Calif.) Register reported in several stories during the past week that former employees of video producer Stuart Karl claimed that they had made donations to the Hart campaign and were reimbursed by Karl, who was a key Hart financial supporter.

It is illegal to give donations in the name of another person. Robert Bonner, U.S. attorney for Los Angeles, said the use of conduits to exceed the $1,000 limit on individual contributions "quite clearly would be a violation of federal statutes." Such violations, however, must be prosecuted within three years.

Bonner could not be reached yesterday, but Justice Department spokesman John Russell said the Federal Bureau of Investigation could investigate whether false statements had been made or fraud committed in getting federal matching funds for Hart's campaigns for the Democratic presidential nomination.

Last Wednesday, the Register also quoted an unnamed former Karl aide as saying that instructions on how to make the illegal donations were given directly by Doug Rosen of Los Angeles. Rosen was Hart's finance chairman for the 1984 campaign. A Hart campaign lawyer said Rosen denied the allegation.

The first report questioning the legality of Karl's support for Hart appeared last week in The Miami Herald, the newspaper that reported Hart's relationship with Miami model Donna Rice. The Herald said Karl paid for at least $15,000 in campaign expenses personally in 1984, put a Hart aide on his payroll in 1986 and provided the candidate with jet and helicopter trips.

The Register quoted two former Karl aides as saying that they arranged to pay other employees in cash to reimburse them for their donations to Hart in 1984. Rama White Middel was quoted as saying, "I was instructed by him {Karl} to get cash and reimburse them."

The Kansas City Star published a similar report about an employer reimbursing employees for donations to the successful 1986 Senate campaign of Republican presidential candidate Sen. Robert J. Dole (Kan.).

{Dole, campaigning in Nashua, N.H., yesterday, said, "We can't keep track of every contribution, so we've asked the FEC to take a look at it," the Associated Press reported. But an FEC spokeswoman said the agency had not received a request for a review as of yesterday, the Associated Press said.}