Biden should have been running ads in Utah. Talking about how Trump doesn't represent [insert something here about "values"], maybe a few clips of Romney and other prominent Mormons or Utahns criticizing him, a clip of the McMullin endorsement. Could have been an even better comparison to Indiana 2008 than Montana or Alaska - a truly deep-R state voting D under "perfect storm" conditions.
Eh, I just find it hard to see actually flipping. A Romney endorsement MAY have made it possible, but short of that I just don’t think it was realistic. Probably something like this, Trump only winning my mid-single digits and Biden in the mid-40s, is the ceiling.