Just when they should be gearing up for the fall campaign, Republicans in two Michigan congressional districts are smarting in embarrassent over two men nominated in their primary Tuesday -- one an ex-Nazi and one a mental patient.

GOP regulars in the 15th district got a shock when their man, James Caygill, was upset by Gerald Carlson, a self-described white supremacist and former Detroit Nazi. District GOP chairman Pat Ganzberger says Republicans will mount a write-in campaign for Caygill, rather than support Carlson, who once taped a telephone message saying blacks should be banned from two Detroit suburbs.

Then comes the 17th district's nominee, Alfred Lawrence Patterson, who turns out to be a mental patient.

Patterson, 25, says he spent $30 to $40 on his campaign and made no public appearances. He didn't even vote -- because he couldn't get out of the mental hospital, where his father committed him last July 14. That came after young Patterson wrote a letter threatening to have Sen. Edward M. Kennedy prosecuted for losing a prison reform proposal he had sent.

So how did Patterson outpoll two other candidates on Tuesday? Patterson was listed on the ballot as "L. Patteron," probably confusing voters with popular Oakland County prosecutor L. Brooks Patterson, and he concedes that "probably helped."

To GOP officials in the district, Patterson remains a mystery man. Said Ed Hartournian, district chairman, "I won't know how much until I can find him."

The two Democratic incumbents in the districts, William Ford in the 15th and William Brodhead in the 17th, are considered shoo-ins this fall.