By Steve Gorman (Reuters) -The gunman who killed three professors and wounded one at the University of Nevada, Las Vegas, was a financially struggling academic whose job applications were rejected by several higher-education institutions in Nevada, police said on Thursday. Anthony James Polito, 67, also had mailed nearly two dozen suspicious letters to faculty at universities across the country and had prepared a “target list” of people at both UNLV and a North Carolina university where he once worked, police said. Polito, facing eviction from his home in the Las Vegas suburb of Henderson, had…