The outlook for the 17 Mar primaries doesn't look good. If Sanders is having problems winning a very progressive state like Washington, I wouldn't expect too much in the more moderate to conservative states of the south and midwest. What you refer to as flyover country.
As of 11 Mar for the primaries on 17 Mar Florida - Biden by 36 Ohio - Biden by 18 Illinois - Biden by 22 Arizona - Biden by 19
then on 24 Mar
Georgia - Biden by 33
It's high past time that we start electing Americans to congress and the presidency who put America first instead of their political party. For way too long we have been electing Republicans and Democrats who happen to be Americans instead of Americans who happen to be Republicans and Democrats.