Toyota: Starting prob., '95 Corolla

Intermittently, the car simply clicks with each turn of the key and
after two or three tries starst fine. Battery is good and terminals are
clean. Car has 120,000 miles. This problem occurred once before and
cleaning every ground terminal and removing the starter and simply
reinstalling the same starter solved it for about two years, now the
problems back. Any ideas as to what ot might be? Auto parts dealer says
Toyota starters rarely go bad and he suspects a connection problem.