Tyler would not describe the attack in detail. It initially appeared to be an ordinary ransomware attack, in which data is made inaccessible unless the victim pays the ransom, usually in harder-to-trace cryptocurrencies. But then some of Tyler’s clients — the company would not say which ones — saw outsiders trying to gain access to their systems on Friday night, raising fears that the attackers might be out for something more than just a quick profit. That has been the fear haunting federal officials for a year now: that in the days leading up to the election, or in its aftermath, ransomware groups will try to freeze voter registration data, election poll books or the computer systems of the secretaries of the state who certify election results. With only 37 days before the election, federal investigators still do not have a clear picture of whether the ransomware attacks clobbering American networks are purely criminal acts, seeking a quick payday, or Trojan horses for more nefarious Russian interference. But they have not had much success in stopping them. In just the first two weeks of September, another seven American government entities have been hit with ransomware and their data stolen. “The chance of a local government not being hit while attempting to manage the upcoming and already ridiculously messy election would seem to be very slim,” said Brett Callow, a threat analyst at Emsisoft, a security firm.