Businessman Louie Sanchez remembers growing up in a trailer in the South Valley where he said he learned the value of hard work. It’s those working class roots he wants to emphasize when he launches a bid for the U.S. Senate on Monday. Sanchez will join a growing Republican field that includes former New Mexico State University professor Gavin Clarkson; anti-abortion advocate Elisa Martinez; and Albuquerque contractor Mick Rich in the race to replace Democrat Tom Udall, who is not seeking reelection to a third term. U.S. Rep. Ben Ray Luján and accountant Andrew Perkins are seeking the Democratic nomination....