What the rich don't like about Democrats is that relatively speaking, the rich slip a bit. Sure the economy grows, but the rich don't quite keep up with the growth of income among the lower classes. They clearly prefer Republican administrations that ratchet back growth but make sure that the lion's share of income growth goes to the very top of the economic pyramid. This is what the really wealthy like. This clearly moves them ahead of the mass of unwashed, undeserving "little people".
For more details about US income distribution, click here for a huge graphic with details.