Prince George's County Executive Lawrence J. Hogan, who is seeking the Republican nomination for the U.S. Senate in Maryland, has raised $108,000 in contributions--less than one-fifth of the campaign war chest amassed by Democratic incumbent Paul Sarbanes.

Hogan has spent more than $93,000 in his bid for the nomination. Another Republican candidate, Montgomery County businessman V. Dallas Merrell, has raised about $43,000 and spent all but about $11,000 on his primary campaign, according to reports filed this week with the Federal Election Commission.

Hogan said yesterday that the huge fund accumulated by the incumbent, who so far faces no major primary challenge, "doesn't bother me because on primary day we'll get a half million from the Republican senatorial committee."

The Republican National Senatorial Committee, which has targeted Sarbanes as the "most vulnerable" incumbent Democrat in the country, has pledged to spend about $300,000, the limit allowed under election laws, on the Maryland race, according Mary Hasenfus, the assistant political director.

"If a credible campaign is going, we are prepared to go in with the limit in funds ," Hasenfus said yesterday, adding that any of the current candidates "could put together credible campaigns."