EL PASO, Texas — President Donald Trump charged ahead with his pledge to build a wall at the U.S.-Mexico border, skimming over the details of lawmakers’ tentative deal that would give him far less than he’s been demanding and declaring he’s “setting the stage” to deliver on his signature campaign promise. In the first dueling rallies of the 2020 campaign season, Trump’s “Finish the Wall” rally in El Paso went head-to-head Monday night against counterprogramming by Beto O’Rourke, a former Democratic congressman and potential Trump rival in 2020, who argued that walls cause more problems than they solve. The rallies across the street from each other served as a preview of the heated yearslong fight over the direction of the country.