  A main issue in improving public sector efficiency is to understand to what
extent public appointments are based on worker capability, instead of being
used to reward political supporters (patronage). I contribute to a recent
literature documenting patronage in public sector employment by establishing
what type of workers benefit the most from political connections. Under the
(empirically supported) assumption that in close elections the result of the
election is as good as random, I estimate a causal forest to identify
heterogeneity in the conditional average treatment effect of being affiliated
to the party of the winning mayor. Contrary to previous literature, for most
positions we find positive selection on education, but a negative selection on
(estimated) ability. Overall, unemployed workers or low tenure employees that
are newly affiliated to the winning candidate's party benefit the most from
political connections, suggesting that those are used for patronage.
