It would have been closer all around the U.S. The south would have been closer but still broken for Goldwater in every southern state. Goldwater would've also won the traditional Republican states such as ND, SD, NE, KS, OK, MT, WY, ID, UT, at the time CO and NM, his home state of AZ, and narrowly won CA. Indiana and Illinois may have also gone for Goldwater. As for Johnson, he was very popular following the Kennedy assassination and would have still won. The country wasn't ready to change leaders for the 3rd time in 14 months. Goldwater wasn't really a hardcore segregationist either. He simply supported the states' rights to decide if they want to have segregation the same as Wallace did in 1968. They weren't as bad as Stevenson, Thurmond, or Byrd.
Stevenson wasn't a segregationist?