Barnes’ decision to drop out came a day after the release of a Marquette Law School poll of Wisconsin Democratic primary voters that found Hong leading Barnes and the other candidates by a significant margin, although about one-third of primary voters remained undecided. The Wisconsin Democratic Party received an anonymous letter in 2024 and again in 2025 making allegations against Barnes, a person with direct knowledge of the party’s actions told The Associated Press. Barnes’ campaign issued a statement saying, “There are no allegations of misconduct or wrongdoing against Mandela.” The winner of the Democratic primary is expected to face U.S. Rep. Tom Tiffany, who faces only nominal opposition in the Republican primary. Barnes ending his campaign comes after he benefited from other candidates dropping out in the Democratic primary race for Senate in 2022 to clear the field for him.