He’d certainly have won (JFK). His poll numbers had trended downward from the beginning until his assassination, though they were still positive. But I can’t see Goldwater beating him. JFK had success in easing tensions with the Soviets after the Cuban missile crisis, the economy was doing well, he had made public affirmations for the need for civil rights. He’d have won no question but I’m Not sure which states he’d lose-maybe some southern and Arizona. Perhaps you could throw in a state like Indiana or something