Switching Parties

[*bfine32*]

I was wondering does an Elected Official have to do anything to change Parties. I remember during the POTUS election talk of a Democrat switching to Republican. Is there anything they have to do (besides in this case throw away his sandals and T-Shirts)?

I ask this for a few reasons: I would love to see Rand Paul admit he's a Libertarian and give some legitimacy to a third party. I read somewhere the other day that Trump is a Democrat.

I know I could google this but then I don't get the insight of others on here or generate discussion. So if you have any insight or can cite examples of someone doing it after being elected please chime in.