If I remember correctly the genesis of that story line occurred when a reporter asked Goldwater what he would do to solve the Vietnam issue. Goldwater responded by saying he would seek an immediate military solution by sending the B-52s to bomb North Vietnam. Senator Goldwater was also a general officer in the USAFRes at that time. I am not sure if his combat strikes occurred after the election or before.
At any rate the media ran with the story and the 1964 elections are history.
BTW - there is one more piece of history that the democrats and the media don't talk about for a variety of reasons. A little over 8 years later, December 1972 to be exact, the US government, under President Nixon, took the B-52s north and bombed North Vietnam back into the stoneage which is what it is reported what Goldwater wanted to do. So if you ever get THE WALL look at all the names that appear between December 1965 and December 1972 and remember who put them there. BTW - the Vietnamese losses were many many times what we lost.
I remember that. The near-universal reaction to that statement was, "Gee, Goldwater is crazy, he wants to drop bombs on North Vietnam!". LBJ and the 'Rats encouraged that notion by either remaining quiet about their intentions, or denying them outright. Oddly enough, within a year of the election, Johnson was doing what Goldwater proposed (dropping bombs). IIRC Operation Rolling Thunder began in March, 1965, so less than a year after the '64 election.