It would have been closer without Kennedy's death IMO, but still a comfortable win. Reagan's likely opposition to farm subsidies destroys him in the Plains, and however sympathetic he may try to be to segregationists, a Southerner is likely to run third-party without Kennedy's martyrdom or a Republican who can point to a vote against the Civil Rights Act. Can also see Reagan overplaying his hand with red-baiting and demanding escalation in Vietnam.
President John Kennedy (D-MA) / Vice President Lyndon Johnson (D-TX) ✓
Activist Ronald Reagan (R-CA) / Fmr. Congressman Walter Judd (R-MN)
Fmr. Governor Ross Barnett (I-MS) / Congressman Bob Sikes (I-FL)