Time to transfer from E gates to C gates at McCarran?
 

I'm looking to take a JetBlue flight to Las Vegas which operates out of E gates and then transfer to a Southwest flight which I understand operates out of C gates. There's an hour and 15 minutes between my JetBlue flight arrival and my Southwest flight departure. Is that sufficient time to get across the airport terminals?

So long as the Jet Blue flight is on time, it shouldn't be a problem. The Jet Blue flight will arrive at Concourse E; you'll then take the tram from T3 to Concourse D (Red Line), the tram from Concourse D to T1 (Blue Line), and then the tram from T1 to Concourse C (Green Line).

... unless your Southwest flight leaves from B gates, in which case instead of taking the Green Line out to Concourse C, use the connecting walkway to Concourse B instead.

Also if your flight is leaving from a C24/C25 you might consider walking down the corridor instead of taking the Green Line tram (it's still ok to take the tram but then you will end up walking back a fair distance along the way you came, doubling back)