The GOP does not have two Presidents (Clinton and Obama) doing record numbers of fundraisers. If all of these conservative $$$ supposedly were not going to the campaign committees to explain the disparity, the candidates and conservative campaign committees should be flush with enough cash to make up the difference - they don’t.
You’re assuming that all the Conservatives who claim that they won’t donate a dime to the GOPe orgs (RNC, NRSC, etc) ARE turning around and donating, at the same level, directly to candidates and the Conservative PACs (Heritage Action, SCF, etc).
I’m not sure thats actually happening. If it was, as you said the money should be there.