Nobody ever gives Liz Warren crap and she voted for Ronald Fing Reagan...
who never gets crap either, even though he was a registered Democrat from the time he was old enough to vote in 1929 until 1962, and a New Deal supporter for most of that period as well. In 1962 he famously said, "I didn't leave the Democratic Party. The party left me."
Kerry's wife was a registered Republican from the beginning of time till her husband ran for president in 2004.
People change. There are plenty of good reasons not to support Hillary Clinton. The fact that she was a Republican before she was a Democrat is not one of them.