Desert Saints (2002) on Netflix

Plot summary

Arthur Banks works as a hitman, mostly for Latin American drug cartels. Solitary women serve as his cover for a job, and he kills them once it is done; his bullets carry a tungsten core. Years of FBI pursuit have taught him to stay in rural desert country, away from the satellites and security cameras watching for him. Agent George Scanlon leads the hunt and wants Banks alive, hoping he will name the men who hire him. Banks picks up Bennie Harper, a drifter leaving an abusive marriage and bound for Paradise, Arizona, and tells her the job ahead will be his last, an assassination of a Mexican presidential candidate. Scanlon and Agent Donna Marbury follow the pair across the Southwest.