Pence is an unknown in NWI. 1st Congressional District knows no republicans. 1st District is the 2nd most populated district in the state and includes cities like Gary.
The people in the 1st District aren't the only ones who get to vote, though. Monroe County and Marion County will be just as tough, but Mitch has won twice now, despite all that.
This is still a red state even if it swooned over the Kenyan in '08. That romance is long gone.