Help with Electrical Gremlin

Quick update. Bad battery connections made sense to me. Currently running an Optima battery which has smaller diameter posts than traditional batteries. And the Optima battery is a couple of years old.
Swapped out to a traditional battery, the car fired up first try however, it exhibited a similar behavior of leaning out before dying.
When I get some time, I will check the wires back to the fuel pump. And check the starter connections.