Well, they weren’t really identified as such (like “Reagan Democrats), but there had to be some traditional Republican voters who supported LBJ in 1964 because he won 61% of the popular vote — it’s still the biggest margin of victory in the popular vote in American history.
Goldwater definitely took the GOP far to the right in 1964 and many moderate Republicans were unhappy with the prospect of voting for him. That — and the civil rights legislation and Great Society progams of LBJ’s Administration shifted the status of the Republican and Democratic parties from that point on. The states of the Solid South — which had been traditionally Democratic since before the Civil War and anti-Republican since the time of Abraham Lincoln — shifted to the Republican column with the appearance of more Conservative GOP candidates. Some of the blue-collar areas of the Northeast, Midwest, and Mountain West, which had been a stronghold of moderate or progressive Republicans for years began shifting to Democratic. When people talk of the two major parties “switching places”, this is what they normally mean. They didn’t necessarily switch places, but they evolved into different versions of what they previously were, largely in the area of social issues.
"LBJ Republicans" would have been traditional Republicans like those in Vermont and Maine who normally went with the GOP but were so turned off by Goldwater that the states not only went to LBJ in 1964 but they’re now solidly Democratic. "LBJ Republicans" could also be found in Midwestern and Mountain West states that had long had a history of electing progressive or moderate Republican Senators. Those Senators also played an integral part in passing LBJ’s civil rights and Great Society legislation that the Democratic Senators from the previously Solid South were vehemently opposed to. As the GOP became more Conservative, many of those progressive and moderate Republicans Senators either switched parties or ended up losing their seats to challengers as the population of their state shifted to the right and further away from their traditional ideology.
JFK would have beaten Goldwater in 1964 — not by the landslide that LBJ won with, but he would have beaten him.
I think that LBJ would have stayed on the ticket. Historians and Kennedy insiders still argue about this, but my reason for thinking this is the very fact that the fateful trip to Texas that led to JFK’s assassination was really a jumpstart to the ‘64 campaign. Texas was very important to JFK’s electoral chances, and LBJ was Texas. Some historians point out that LBJ had become unpopular in Texas during his Vice Presidency, but I just don’t think JFK would have taken that trip and had such a big role for LBJ on that trip (JFK was supposed to stay at the LBJ Ranch on the night he was assassinated) if LBJ was going to be dumped from the ticket.
According to Robert Caro’s most recent volume of The Years of Lyndon Johnson, The Passage of Power, Evelyn Lincoln, JFK’s faithful secretary, says that Kennedy told her — just a few days before the assassination — “I will need as a running mate in ‘64 a man who believes as I do…It is too early to make an announcement about another running mate —- that will perhaps wait until the [1964 Democratic National] Convention.” She also says that JFK mentioned that he was considering North Carolina Governor Terry Sanford as his running mate, and that President Kennedy emphatically said, “But it will not be Lyndon.”
However, Arthur Schlesinger, Jr., a Kennedy aide and eminent historian, wrote that there were no plans to dump LBJ from the ticket and that “The non-existence of any dump-Johnson plan is fully and emphatically confirmed by Stephen Smith [JFK’s brother-in-law].” Schlesinger wrote that “Johnson’s place on the ticket was not discussed [at the first strategy meeting for the 1964 campaign] on November 13  because (barring illness or scandal) it was a given.”
Mrs. Lincoln was a loyal public servant and totally devoted to JFK, but I tend to side with Arthur Schlesinger on this one.
It wouldn’t have changed things. First of all, LBJ had gained the nation’s confidence in the weeks after JFK was killed by smoothly taking the reins of government and then using his unparalleled political skills to push through a significant amount of legislation that had been mired in Congress during the Kennedy Administration. If Goldwater had voted for the Civil Rights Act of 1964, it would have just been another vote for Lyndon Johnson’s legislation.
Secondly, Goldwater frightened people with his hawkish speeches and his Conservative agenda. It wasn’t what the nation wanted in the early-mid 1960s. At times, Goldwater was out of touch with sections of his own party. Plus, he wasn’t a very good campaigner — a huge disadvantage due to the fact that he was facing one of the very best.
What is most overlooked about 1964, however, is that the country had just changed Presidents in November 1963 when Kennedy was assassinated and LBJ assumed office. Whenever we transition from one President to another it is a big change, particularly when it’s a shocking, horrible tragedy like JFK’s assassination. Electing Goldwater in November 1963 would give America three Presidents in just over a year. The nation didn’t want that. It wanted — and needed — stability. Even Goldwater knew that. As a political realist, Goldwater recognized that his chanced at the White House in 1964 was pronounced dead as soon as John F. Kennedy was. At no point after Kennedy’s assassination did Goldwater realistically think that he would be elected President in November 1964.
I think Goldwater would have had a better chance in 1968 than 2012, but I don’t know if I can envision a scenario where Goldwater could ever win 270 electoral votes. McGovern, I believe, would have an easier time today because what he was in 1972 was really a sneak peek at what the Democratic Party would become in the 1990’s until now.
I will say this about Barry Goldwater — while he certainly scared the crap out of a lot of people in 1964, there were a lot of other factors that played a big role in LBJ’s landslide victory. When people went to the polls in November 1964, they did so less than a year after JFK’s assassination. With everything going on in the world, there was a hunger for political stability and LBJ offered that. Americans didn’t want to have three different Presidents in a span of less than 15 months. Even Goldwater knew that. He went into that 1964 campaign knowing that JFK’s assassination had all but guaranteed that Goldwater was fighting a losing battle.
Don’t get me wrong. LBJ’s effective assumption of the Presidency and his efficiency in working with Congress to get things accomplished from November 22, 1963 until November 3, 1964 also had a lot to do with the landslide. And Goldwater was too extreme for a lot of Americans. But the 1964 election would have been far closer had John F. Kennedy been seeking a second term against Barry Goldwater. Kennedy would have won, but there’s no way he would have won 61% of the popular vote like LBJ did in 1964.