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Sen. John McCain is #2 in the eyes of former Trump adviser Roger Stone -- and no, he doesn't mean second place. 

Stone was at Politicon Saturday in Pasadena when we asked if he thought President Trump would be able to get past McCain's skinny repeal 'no' vote.  He says no way, and even further ... makes it clear he doesn't think the Prez should let it go. 

Truth is ... Stone's been blasting Sen. McCain everywhere since the vote, but this time he's amping up the rhetoric.  It's uncommon to see a senior senator/war hero spoken of this way.