Intellectual who supports a political party in return for benefits

Solution 1:

A shill is a tout or promoter, with the connotation of figure who endorses a product or service— or candidate or party— on a supposedly independent basis, when in fact he or she is in the service of the person or organization benefiting from the endorsement.

Solution 2:

A related phrase is fellow traveller,“One who sympathizes with the aims or beliefs of an organization, without belonging to it; most often applied to a Communist sympathizer”. Technically, the phrase applies fairly well in the current context, except that people are unlikely to automatically suppose a fellow traveller is an intellectual or a journalist or secretly receives benefits.

Depending on context, also consider nouns collaborator and quisling, and phrase tame journalist.

Solution 3:

partisan (noun) an adherent or supporter of a person, group, party, or cause, especially a person who shows a biased, emotional allegiance. (Dictionary.com)