Why not? That strategy worked out extraordinarily well in getting conservative support for Donald Trump four years ago, when that wing of the party still distrusted his commitment to conservative issues and agenda items. Joe Biden faces a similar problem in reverse this year, with the populists skeptical of his long establishment mentality.
Are they just worried about Biden’s delivery? Because that might be legit, but hardly limited to his Supreme Court list:
"You know the rapidly rising umm uh in with uh with I don't know." – Joe Biden. pic.twitter.com/WQMkgISM1D
— Francis Brennan (Text TRUMP to 88022) (@FrancisBrennan) June 11, 2020