It’s either intention or it’s another instance proving the online poll people right, that landline/cell polling leaves to many out.
There’s another option as well: the KY GOP has a GOTV machine that the polls can’t account for.
What we may be seeing here is the same situation, with the parties reversed, as 2012 where it looked like Romney was going to win.
Obama’s GOTV machine (Catalist, Narwhal) focused on getting people on the left who normally didn’t vote to the polls. Instead of moving to capture moderates/centrists.
We now have back to back years of KY polls massively underpredicting GOP turnout. Good evidence of something happening that the polls are completely unable to capture.