How many states do I border?
Mathematica, 112 111 bytes
-5 byte thanks to Mark S. and LegionMammal978!
-22 bytes (and noticing a problem with the output) thanks to ngenisis!
Tr[1^Entity[&quot;AdministrativeDivision&quot;,#~StringDelete~&quot; &quot;]@&quot;BorderingStates&quot;]+Boole@StringMatchQ[#,&quot;Il*&quot;|&quot;Mic*&quot;]&amp;

Of course, there's a Mathematica builtin for it. Includes D.C. in the count.