I've never used the words “mudslinging” or “dirty work”, but I would say that groups like Leadnow and the Dogwood initiative influence elections primarily in two ways. One is by what you might call framing the narrative, establishing the issues on which the election is fought. The second is by targeting first-time voters, people who have never voted before, young people especially, and getting them out to vote.
On October 16th, 2018. See this statement in context.