At the beginning of the guberntorial campaign, the media consultant for Acting Gov. Blair Lee III said that Lee would spend $500,000 on a "media blitz" during the Democrat's primary.

Yesterday, Tony Schwartz, the Manhattan advertising executive hired to produce Lee's radio spots, said he had stopped working for the Lee campaign because it owed him too much money.

"He's the only client with whom I've had this payment problem," said Schwartz, a nationally recognized expert on political advertising. "He's not making his payments and . . . he can't authorize going further, he can't pay future bills."

There was disagreement within the Lee campaign yesterday whether the campaign treasury could afford to pay Schwartz immediately and whether it was necessary. It was a disagreement as much on strategy as the financial health of the campaign.

Frank A. deFilippo, Lee's media consultant, said everything had been worked out, that Schwartz is to be paid shortly and immediately get back to work on radio advertisements. There was no problem with money, he said.

"We're entering the critical last six weeks of the campaign and this is when the big push with media has to be made," deFilippo said. "I think it's crucial."

Blair Lee IV, campaign manager for his father, disagreed with deFilippo. He said there was a "little problem" with money but that the debt of "several thousand dollars" owed to Schwartz was not being paid because he did not feel his father needed radio advertising now.

The younger Lee, who controls the purse strings of the campaign, said "you cut back where you can. Until we use radio we aren't going to pay."

He refused to say exactly how much money is owed Schwartz or how much money is on hand in his father's campaign chest. "That's part of our tactics, our strategy . . . we don't have to disclose our disbursements yet."

Under Maryland law, details of the expenditures of a campaign do not have to be made until one week before the Sept. 12 primary.

Besides, the younger Lee explained, he saw no reason for radio advertising soon. "Because we're the incumgents, with incumbent name recognition, we don't need the media campaign now. It's vacation season."

According to reports filed last week, Lee has collected $450,000 for his campaign and is the leading fund-raiser among the Democratic candidates.

Lee also is the frontrunner in the polls.

"I'm conservative," the younger Lee said. "Why give somebody a big chunk of money when it is not needed? Schwartz doesn't bother me. The people coming from behind need the name recognition, not us."

This week, Baltimore County Executive Theodore G. Venetoulis, Lee's strongest competitor in the Democratic primary, according to the polls, began broadcasting radio advertisements. Harry R. Hughers, another Democratic candidate, began his campaign with television advertisements in the Baltimore area.