At least 93 immigrants in the Tucson area alone have died  this year of heat and dehydration, or hypothermia in the winter,  while trying to make the trek. The toll already surpasses last  year's total of 76 for the area, according to the U.S. Border  Patrol. The agency's records show that more than 1,000 have died on the U.S. side of the 2,000-mile-long southwest bordern with  Mexico since 1998.