George Nesterczuk, associate director for administration at the Office of Personnel Management and the man who ran President Reagan's Maryland campaign two years ago, will become the third person to manage the senate campaign of Prince George's County Executive Lawrence J. Hogan.

Hogan, who is virtually assured of winning the Republican nomination in the Sept. 14 primary, is seeking to unseat incumbent Maryland Sen. Paul S. Sarbanes, a Democrat. In July, Hogan fired his first campaign manager, Michael Hoback, and brought in Republican National Committee staffer Mary Hasenfus as an interim manager.

Hasenfus's job, according to party officials, was to "straighten out the campaign." Two weeks ago, Hasenfus, as planned, returned to her job with the RNC's senatorial committee. That committee is expected to pump $250,000 into the Hogan campaign as soon as he becomes the party's nominee.

Nesterczuk, whose conservative philosophy is similar to Hogan's, will resign his federal job on Friday and take over Hogan's campaign after Labor Day.

Sources in the Hogan campaign said Nesterczuk had been Hogan's original choice for the job even before Hogan announced his candidacy. Nesterczuk, who had just joined OPM at that time, was not interested in leaving his new job so quickly, the sources said.

Nesterczuk, 37, was active in the conservative Young Americans For Freedom during his college years and worked in Sen. Barry Goldwater's 1964 presidential campaign. He has been involved in Republican politics in Maryland for several years.

Nesterczuk said yesterday that his first priority will be to raise money for a media campaign. "Without it, we won't be able to take the state," he said.

The Hogan campaign has had difficulty raising money. In July, the last time that candidates were required to file financial disclosure reports with the Federal Elections Commission, Hogan reported he had raised $212,000. Early this month, he said an additional $65,000 had been raised. Sarbanes has raised more than $750,000.

Hogan has worked feverishly to tie himself to the Republican National Committee, knowing that the party's senate committee can pour needed funds into his campaign and help tap political action committees around the country.

Nesterczuk said he believes that both political action committees and individuals have been "holding back, waiting until after the primaries." Nesterczuk estimated that Hogan's campaign will cost $1 million.

Hogan should be able to raise $700,000 through PACs and fund-raisers throughout the state, according to Nesterczuk.