1997 Pontiac Sunfire Won't Start

Engine Mechanical problem
1997 Pontiac Sunfire 4 cyl Automatic 104599 miles

We've been having troubles with the engine starting, I'd turn the key and get nothing, not even a click, but then I'd jiggle it around and try it again and it would start right up. It happened mostly when it had been raining out. Then, once I'd get it started, the Check Engine light would come on and I'd get multiple sensor codes, but once the car dried out, the light would go off and it would run fine.

Then, a couple weeks ago, it did that, and I tried to start it twice, but nothing happened, so I was calling someone to come get me, and AFTER I took the key out of the ignition, it started.

And sometimes when I'm sitting at a stop light, it will act like it's going to die, but would be fine when I gave it more gas.

THEN, last night, it started fine when I got out of work, and fine when I picked up my daughter, but then we went to pick up my husband and when I came out 3 minutes later, it wouldn't start at all. When I turn the key, the dummy lights all light up, the interior light dims, and then. Nothing. Not a sound. It's not even TRYING to crank. My brother came and knocked on the starter and we got one click, but then nothing happened.