I'm planning a trip to SFO. To have some fun I decided not to take the shortest way. May plan is to fly PAD-FRA-PDX-SFO on LH and UA. On my way back I want to fly SFO-DEN-FRA-PAD on UA and LH. Only the us-domestic flights are on UA. This is a good choice of various aircrafts and would be my first time on an us-domestic flight and on an us-carrier.
My time at PDX will be 1:11 hours. My time at DEN will be 1:12 hours. Is it enough to change aircraft and to deal the immigration dept. at PDX?
Thanks for help.