The fact of the matter is, no one is going to care about some 'Politico article."
What people remember is that trump made the biggest "thing" about it, since the invention of sliced bread.
And besides, just because someone else started the rumor, doesn't excuse trump for believing in something so stupid (Obama birtherism), and then shouting like a crazy idiot in the streets that the sky is falling !
Do you understand ? ..... trump looked like a total clown when he did this.
It does matter when the person who sowed the racist seeds of doubt in the first place is the person he is literally running against. It matters that it's out of Politico because like Hillary's emails, it's not some right-wing smear out of Drudge or Breitbart, it's out of the liberal media. Trump isn't going to willingly go there, as he has nothing to gain, but Clinton damn well knows that if she goes there, he will hit her back. Clinton's hit him on just about everything already, and if she thought going there would be a net benefit for her, she would have.
If you hear a rumor (even if the Dems created it) that someone is half human and half Martian, you don't go around making a huge stink about it to the press and to the entire world (and demanding proof with birth certificates). The electorate is looking at you, saying "what the hell is that guy (trump) smoking ? !"
And then later say, "well it's not really my fault, I didn't start this. I didn't start this rumor."
"Please forgive me for acting like a crazy-ass idiot."
This is almost equivalent to what happened.
No other politician went down the "trump road" with this.
They all knew that if you did, you would just look nuts.