Large public demonstrations have historically done more damage to their supposed sympathizers in office than good. Anti-War protesters haunted Kerry in 2004 and Johnson in 1968, and I suspect hurt W. J. Bryan in 1896. This is exactly what a Republican trying to win Indiana, Virginia, Ohio, or North Carolina wants to see. (Coincidentally, these movements linking itself to celebrities is doubly dangerous. Various unions brought in Hillary Swank and Brendan Fraser to stump for the Democrats in Ohio in 2004 and it turned out to be a total disaster).