> cannot be attributed to a party allegiance in the US. There are as many if not more liberal vaccine refusers as there are conservative ones

Why must there be a single attributable factor? It seems likely that there are multiple. Party allegiance certainly appears to be one of these from numerous polls and analyses [1]. Poverty and insurance status is likely another [2].

[1]: https://www.kff.org/coronavirus-covid-19/poll-finding/import...

[2]: https://www.kff.org/coronavirus-covid-19/issue-brief/vaccina...