A person who is part of a coalition or who advocates for coalition-building and cooperative politics.
From coalition + -er (agent noun suffix). The -er suffix denotes someone who performs an action or belongs to a group. This term is relatively modern, emerging in 20th-century political discourse.
Coalitioners are the political bridge-builders—they're the ones skilled at negotiating with rival parties, which might be even harder than winning an election solo!
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