What was a team of seven has grown to 25 - programming the election computers, and checking the identities of people registering, to prevent multiple voting.
For a year before the election, the computer supervisor, Christopher G. Seidel, worked from campaign offices and had virtually no Congressional duties, Ms. Cassidy is said to have testified.
Before the election, Rice University computer science professor Dan Wallach told MIT Technology Review that poorly secured voter registration databases were the biggest cybersecurity threat facing the U.S. voting system, since many states put them online.
To prove a conspiracy, former prosecutors said, Mr. Mueller's team would have had to show that Mr. Trump or one or more of his associates agreed that Russia should interfere in the election through computer espionage, illegal use of social media or other criminal means.
The terrorist attacks in Mumbai played out not only on cable networks but for the first time since the election on computer screens.
The administration put heavy pressure on the Fujimori government to hold a runoff after international monitors reported during the first-round vote that ballots and tally sheets had disappeared and election computer centers had shut their doors without explanation for many hours at a time.
In six states, they went further, trying to gain access to voting websites, and in "a small number of states" actually breached election computer defenses.
The emails concealed a computer script that, when clicked on, "very likely" downloaded a program from an external server that gave the intruders prolonged access to election computers or allowed them to search for valuable data.
CNN Anchor Jake Tapper on Friday incorrectly said the U.S. was accusing the Russian government, not a company, of threatening election computers.
Michael Harty, who suggested that programmers of election computers should be licensed, emphasizes the little-known fact that most state election laws are not mandatory but "directory," and levy few or no penalties against officials who do not obey them.
