Performer 405 - Engine turning but doesn't want to fire up

Hey guys, I have a bit of a situation with my Performer 405 (A-12).

For the last few days I'm having a hard time getting it to fire up. It cranks and cranks, and occasionally it will fire up but only for a split second and then immediately dies.

I'm occasionally able to get it going if it fires and I slide the throttle arm around until it "takes". I immediately thought fuel, so I put some gas directly into the carburetor throat, but it's pretty much the same deal... it will fire, but...

Performer 405 - Engine turning but doesn't want to fire up