After four years in exile, the prediction market platform Polymarket has begun a well-funded campaign to sell a new version of itself to the American public. To do so, the company is trying to convince policymakers, regulators, the public and prospective customers that the business it is building onshore is a more disciplined operation than the freewheeling offshore exchange that has at times been the subject of unfavorable headlines. Polymarket has hired social media influencers to produce vira