A tabloid publisher, American Media Inc., told prosecutors that the president’s lawyer and at least one Trump campaign member helped hatch the plan to buy and bury such stories more than a year before the election — and federal prosecutors in New York are continuing to investigate. The hush-money case was referred to federal prosecutors in New York by Special Counsel Robert Mueller’s team, who have unearthed a raft of other legal problems while pursuing possible collusion with Russia. Other authorities are asking questions about at least two more campaign issues: the improper use of money by the Trump Foundation in Iowa, and the possible coordination of messaging with the National Rifle Association.