If it is only happening when you turn the cruise on, and it goes away when you turn the cruise off, I don't think it is the coils or spark plugs. If it was a coil or spark plug, I don't think setting or turning off the cruise control would have any effect unless you are going up hill and it is under load.
The cruise system utilizes some items which send or receive electrical inputs or outputs. These include the brake pedal position sensor, the body control module, and the engine control module, along with the buttons on the steering wheel and the accelerator pedal. A poor connection or problem with any of these could interrupt any signal being sent or received, and may cause the car to jerk or miss perhaps.
If you are in cruise and it is missing, what happens if you leave it in cruise but accelerate by pressing on the gas pedal? This action should override the cruise system and show if there are any misses or not while accelerating.
You could also stop at a parts store and have any codes read which may be stored in the computer. There are specific codes for misfires, and also for cruise control malfunctions. Many parts stores will read the codes for free since you are not in California.