Jim Gibson and Gregory Caldiera has posted this draft on SSRN (Journal of Empirical Legal Studies).  Here is the abstract:

Legal scholars have of late become quite worried about how citizens form their impressions of the fairness of courts. This concern reflects the changing environments of courts, especially elected state courts, and what might generally be termed the politicization of the judiciary. The purpose of this article is to assess the effectiveness of judicial recusals at rehabilitating a court/judge tainted by perceived conflicts of interest associated with campaign activities by litigants. Based on an experimental design embedded in a nationally representative sample, our data first confirm that direct campaign contributions undermine perceptions of fairness; but, unexpectedly, so, too, does independent support for the candidate. Most important, recusal does indeed restore some perceived fairness; unfortunately, the repair to public perceptions is not to the level enjoyed when no conflict of interest exists. In a post‐Citizens United world, these findings therefore point to significant threats to the legitimacy of elected state courts.