Sure, I believe there is a reason that CIA-oriented conspiracy theories are the rage while more plausible ones, like the Mafia, get short shrift. The Morley-Newman-Di Eugenio wing of Conspiracy World epitomizes this. These are mostly extremely left-leaning characters who believe the country has gone to hell in a handbasket since the JFKA and that we'd be living in a near-utopia if JFK and RFK had lived. They have elevated JFK and RFK to near sainthood, even to the extent of imagining policies and accomplishments that simply aren't true. The theorizing almost works in reverse: the country has gone to hell since the JFKA, hence the Dark Evil Forces responsible for this "must" have been responsible for the JFKA. I think they are less interested in the JFKA as a historical event than as a validation of their worldview. Plus, of course, elaborate CIA-type theories are simply more fun than some mundane Mafia hit. The LN narrative, of course, is completely unacceptable since it explains and validates nothing.
I started a thread on this topic at the Ed Forum after I'd been a member only a short time because what I was observing was so screamingly obvious. Suffice it to say, it wasn't popular.
I think it's interesting that those leftists who
don't believe there was a conspiracy are also people with a critical view of JFK, people who don't see him as a transformative president. No Camelot for them with JFK. Think of a Chomsky, the late I.F. Stone and a few others. These are or were hardcore leftwingers but they viewed JFK as another Cold War warrior who was behind the Cuban covert war (recall Stone's statement after the assassination?) and simply wasn't going to just leave Vietnam (he wasn't) or dismantle the containment policies of the post-war period.
Those on the Left, however, who do view JFK as "one of ours", as someone who was going to expose the "war state" (as Garrison called it) and end the Vietnam war, normalize relations with Castro - that is, someone who was essentially going to, as they saw it, take democracy back from the right wing militarists who stole it after WWII - are really the ones who see the CIA behind it all. That's Stone, Morley, DiEugenio, Douglass, et al.
It's ironic that the real question that divides the CT/LN sides isn't just "Who was Lee Harvey Oswald?" it was "Who was John F. Kennedy?"