In a state where colleges struggle to recruit a diverse student body, New England College in Henniker reports that currently 36.2 percent of its 1,135 resident students identify as African American, Hispanic, Asian or more than one race. Michele Perkins, who has been the college’s president for 14 years, said that at one time people told her the goal of campus diversity in a rural area of the Granite State would be “impossible or very difficult.” “I didn’t believe it,” she said.