Dear sjsheppard4,

Hope you're well. Some possibilities:
(a) clean both battery cable clamps. Especially on the + (red) side - where there are multiple cables attached to the clamp, the threaded shaft - that clamps the cable terminal to the battery post - can become corroded in places not easy to see without taking apart the assembly. The - (blue) side also should cleaned.

(b) clean the starter cable connections. An aerosol corrosion-remover (Deoxit or similar) removes corrosion. Sometimes an invisibly-thin layer of corrosion suffices to disrupt a circuit.

Further, by "ignition" do you mean the ignition switch? How many miles on the starter?

Hope this helps.

Yours faithfully,

Spook