If the LP became a major party right now, whom of both parties would shed their current label and switch to the newly powerful Libertarian Party?
Well, as in that case either Republicans or the Democrats would no longer be a major party (constitutionally, only two major parties are allowed in the US
- yes, I mean it
) - there would have to be many. Of course depending on those who switch, the ideology of the Libertarian party mainstream would change. Probably, at least 99% of the Libertarians at that point would not support policies you consider Libertarian
In fact, if that happens the word Libertarian would completely change its meaning.