vendermen

A person or speaker that has said one or more contradictory statements in the past to statements they are making currently, but because they are currently saying things you agree with you feel compelled to be on there side, like, admire, appreciate them, or agree politically.

Your feelings continue with full knowledge that the speaker may not believe anything they are currently saying and may have just picked a side politically. Also, a key factor is you know they may be an opportunist.