How the G.O.P. Primary for Mayor Turned 2 Friends Into Bitter Rivals Two long-shots, Curtis Sliwa, the founder of the Guardian Angels, and Fernando Mateo, a restaurateur, are in a heated fight to be their party’s nominee. Curtis Sliwa, left, and Fernando Mateo are running for mayor on the Republican ticket.Credit...Photographs by Andrew Seng for The New York Times Published May 25, 2021Updated May 27, 2021 The two Republicans running for mayor of New York City used to be friends. They are both first-time candidates, long shots for the job and tabloid fixtures who perk up when they see a news camera.