Just wow--this is a letter from a Dallas citizen begging JFK not to visit:

[HooptieWagon]

2. Yes, Dallas was a hotbed of conservative extremists,...

...the John Birch Society was big there. And there was a lot of conservative agitation being stirred up by former Gen Edwin Walker, who was fired for passing out JBS pamphlets to personel on base in Germany. This was the same Gen Walker that Oswald tried to kill earlier in the year.
Also, the Texas Dem Party was deeply divided between the liberal faction headed by LBJ and Gov Connelly, and a conservative faction headed by Ralph Yarborough. A main reason Kennedy went to Texas (besides fund-raising) was to heal the rift. However, it appeared to deepen it as the two factions bitterly fought over the details of the trip. Connally prevailed, and he was behind the last minute change in location of the fund-raiser to the Trade Mart, which necessitated the motorcade taking the dog-leg from Main to Elm, as Elm was the route to the Trade Mart. The Trade Mart was selected becaise it was much smaller than the previously scheduled location, and lack of space could be used as an excuse to exclude the conservative faction and their wives (all the pol wives wanted to be seen and photographed with Jackie).