Interesting, I never really trust someone who was an elected Democrat and then switches to the GOP. They still bring a lot of their liberal beliefs with them.
My thought was, as we have discussed, the Democratic party is no longer that. It is the Socialist/Communist party. They could NOT start a third party and label themselves that, so they co-opt what the dems used to be (which was pretty bad at being the nanny state and breeding government dependency.)
This might be what we are seeing with Trump's numbers increasing... it could be a larger wave in 2020, or more people may have been turned off by Trump's brash ways and vote against that, not caring about electing a socialist/communist. Could go either way depending on the chosen one from the democratic primary.