And a fine job the FBI did "investigating" it. Using an unvetted dossier to get a FISA warrant, to spy on a member of a Presidential candidate's campaign without letting the FISA judge know that it was paid for by the opposition candidate and that it was unverified. How many procedures were broken there?
As far as 'turning it over to the FBI", do politicians turn over all the "trash" they receive regarding any candidate without checking it out first? If so, there surely must be a ton submitted about the Clinton's, no? A fine job the FBI has done investigating her. Compare her standard of investigation to that of say, Michael Flynn. . .
IYAM, I think McCain gleefully brought this stuff forward due to the animus he had regarding Trump. This was not a call of duty but a petty, "gotcha".