WASHINGTON—Newly declassified documents illustrate attempts by foreign actors to influence U.S. elections and by some American intelligence agencies to downplay election-related connections. “I’m basically running a shadow government across the FBI at this point,” FBI agent Nikki Floris wrote in 2020 to a colleague whose name was redacted from the files, amid disagreements between various analysts and agencies about how best to frame intelligence reports related to the Chinese Communist Party’s (CCP’s) role. The documents were released by the White House on July 16 during President Donald Trump’s primetime address to the nation. A long-time intelligence analyst for the FBI, Floris served as the agency’s election security lead for the 2020 elections. She was also managing all intelligence and strategic functions for the FBI’s counterintelligence program....