One of the reasons that election administration in the U.S. is so complex and, at times, chaotic, is that the system was designed to be decentralized. The following is from a committee report for the 2002 Help America Vote Act.
The dispersal of responsibility for election administration has made it impossible for a single centrally controlled authority to dictate how elections will be run, and thereby be able to control the outcome. This leaves the power and responsibility for running elections where it should be, in the hands of the citizens of this country. Local control has the further added benefit of allowing for flexibility, so that local authorities can tailor their procedures to meet the demands of disparate and unique communities. Further by leaving the responsibility for election administration in the hands of local authorities, if a problem arises, the citizens who live within their jurisdictions know whom to hold accountable. The local authorities who bear the responsibility cannot now, and should not in the future be able to, point the finger of blame at some distant, unaccountable, centralized bureaucracy.
That quote is from a letter send last week by congressional leaders urging states to be vigilant about hackers attacking election systems