Biden has taken the lead in Washington State with 76% of the votes counted.

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.