Someone involved in the media, almost always a major outlet, who attempts to "spin" events and predictions in a certain light in order to further their agenda.

Communication professional that crafts messages on behalf of an organization or individual to persuade an audience

An operative who uses his platform to influence the perception of a person, organization, or event. Like a damage-control PR person.

Most often this is in the political context, usually conservative, with the spin doctor masquerading as a journalist or "expert in the field" to lend credibility to what's actually just a PR line cooked up by the right-wing.

A political analyst, pundit, or anyone else who makes their living by "spinning" something to make the other party look bad and their party look good. Some even resort to all

Someone who manages the media for a politician or political party, to the extent of manipulating policy and behaviour for the sake of image.

The role was typefied
(some might say invented) by Tony Blair's 'Director of Communications and Strategy' Alastair Campbell.

bushfuck and/or his official liar.

Drug dealer, particularly speed.