Police in Tempe, Arizona have arrested a man they believe is responsible for a spate of shootings at a Democratic field office in the pivotal battleground state. The alleged shooter’s cache of weapons and ammunition suggests he may have been planning a politically motivated mass shooting. Phoenix-based ABC affiliate KNXV reported Wednesday that 60 year-old Jeffrey Michael Kelly has been arrested in connection with three different shootings reported at the campaign office since September. Democrats have since closed that office and moved operations to an undisclosed location out of concern for …