Albert Martinez, a 70-year-old Democrat from San Diego, Texas, voted for Trump in 2016, but he now believes the Trump administration has “gone amok.” The Army veteran said he is a proponent of getting criminals out of the country, but that is not what he is seeing happening with current immigration enforcement. “They started doing everybody across the board,” Martinez said. “Innocent kids and women, people who work in restaurants, people who work in hotels, people who are building homes, people who are doing masonry work, and innocent, good, taxpaying people. Taxpayers. It’s insane.” Immigration has been a demographic lifeline for much of rural America. Rural areas have been losing young adults for years, she said. “For a lot of small towns, immigrants are the reason the school and hospital stayed open and the county didn’t shrink,” Monnat said. About 7 in 10 rural voters see immigrants who are in the country legally as “very” or “somewhat” important to their local economies, and...