Kenmore refrig goes completely off, bumping restarts it

My 10 year old Kenmore refrigerator, model 106.70287990, cools and freezes, but just developed a problem with an internal electrical component somewhere. Last evening the refrigerator went completely out (no lights or compressor running). After I moved it out from the wall and "bumped it" a bit, it restarted and ran perfectly, cycling on and off normally, until this morning. Same problem again. I moved it out again, unplugged it, removed the back panel, and "thumped" the "start-device" and "capacitor". The compressor was not warm to touch. I plugged it back in and it started, including the compressor cooling fan. Could a problem with the start-device or capacitor cause the lights and all to go out?? If not, any ideas? Thank you.