Meet the G.O.P. Personal Injury Lawyer Buying His Own Trump Ads

Late last week, a series of TV ads began running in Pennsylvania blasting Kamala Harris’s record on law enforcement and immigration.

In one, Mark Lamb, the sheriff of Pima County, Ariz., widely known for his election denialism and hard-line stance on immigration, slammed Ms. Harris on border security. Another called the vice president “a radical liberal” and falsely claimed she “massively defunded the police.” A third ad, set to debut on Monday, features the National Football League hall of fame quarterback Brett Favre offering a dire assessment of current world affairs.

For audiences in a crucial swing state, the pro-Trump spots might seem unremarkable — just more mudslinging between episodes of “Access Hollywood” and “America’s Got Talent” during the presidential race’s homestretch. But unlike the ads pumped out by candidates and big-money super PACs, these spots were paid for and produced by a single person: a Trump donor named Dan Newlin.

Mr. Newlin — a publicity-loving personal injury lawyer in Central Florida — has paid for more presidential campaign advertising this cycle than many advocacy groups or professional organizations.

So far, he has outspent the abortion rights group Reproductive Freedom for All and the National Association of Manufacturers, according to the media-tracking firm AdImpact. He is not far behind what Robert F. Kennedy Jr. and Representative Dean Phillips of Minnesota spent on advertising during their presidential campaigns.

Mr. Newlin is motivated, he says, by concerns about the country’s direction under a Harris administration, but also by the desire to micromanage the millions of dollars he has poured into politics over the past year. He relishes the opportunity to put himself in the middle of