clicking starter

1991 4x4 blazer clickign starter seems to do it more when truck is hot.  Have to keep turning the key to get it to engage any ideas hoping it is easy

I would guess that the starter motor brushes are worn out and the starter is about to fail completely.
Check the battery voltage and load test, if it's ok, replace the starter.

Very typical indication of a starter getting ready to die. By the way, you can try smacking it with a hammer when it doesn't like to work. I've gotten 5 months out of starter doing that. But expect to replace it soon.