captive candidate
noun
- one who is allegedly "owned" by special interests or political groups
Wiktionary
noun
- A political candidate who is under the control or influence of another person.
“Fortunately — very fortunately — the American people have a happy alternative to this bankrupt Republican campaign and its captive candidate.”
“I want to start with an immediate and firm disclaimer. Walter Mondale is not a captive candidate of the “special-interest bosses of labor.””