It looks like some Republicans are starting to become unglued. I just received information that this past Friday, vandals targetted the Democratic Party's Headquarters in Tucson. Police haven't made any arrests yet, but the investigation is ongoing. The vandalism was clearly designed to interfere with campaign activities, as for example phone lines used for canvassing voters were cut and this has pointed suspicion directly at someone who wants the Democrats to fail.
This sort of thing is inexcusable no matter who is doing it, or who they are doing it to (for example, I also condemned at the time the tire slashing of some vehicles at a GOP headquarters in Wisconsin on election day of 2004 which delayed giving some voters rides to the polls.)
However, this also seems like a desperate act. With the Republicans nominating an extremist with high negatives who is now down 10% in the race for the (currently Republican) open Congressional seat in southern Arizona, it seems they are starting to resort to dirty, dangerous and illegal tactics.