How is that different from the what the DNC, the Hillary Clinton campaign (Christopher Steele/Fusion GPS/Ukraine/direct agents of Russian intelligence), and what Democrat senators Leahy, Durbin and Menendez did, that I linked above?
The only Trump supporters who are voicing doubts are the Establishment/never-Trumpers in the GOP who have previously never missed a similar opportunity to attack Trump.
Trump still has an unprecedented 95% support from his Republican base, who are not buying it, and are not leaving Trump.
As Kim Strassell of the Wall Street Journal said, there is nothing Democrats are accusing Trump of, that the Democrats themselves have not done, and egregiously more so.
