The State Supreme Court overruled a Commonwealth Court decision allowing Bob Guzzardi to stay in the race.
The Commonwealth Court had ruled that despite the fact that Guzzardi failed to file his required statement of financial interests with the state Ethics Commission on time he could stay in the race.
However The Supreme Court found that his failure to file a timely statement is a "fatal defect" that ends his candidacy.
This means Governor Corbett is the only Republican now on the ticket for the May 20th primary.
Four candidates are vying for the nomination from the Democratic Party.
Copyright 2015 Nexstar Broadcasting, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.