Well millions of Americans supported Obama.
Yes they did and after 8 years of Obama, why the other side is now coming out supporting Trump, en mass.
You might have noticed this.
And every vote counts if one wants to win. If the candidate is not likable, and does not resonate with voters, it is recipe for defeat in elections. After losing an election, it matters little how good conservative the candidate is, he/she becomes totally irrelevant to advance any conservative agenda.