The second Dan Sullivan on Alaska's Senate ballot has left his hometown, multiple sources told CBS News on Friday, four days before Alaskans finish voting in a race that could decide control of the Senate.

Daniel J. Sullivan, a retired Petersburg schoolteacher running as an independent against Republican Sen. Dan Sullivan, was seen on a flight to Anchorage on Monday by a resident and former student, who told CBS she didn't know where he was headed. That was two days before the New York Times reported that operatives linked to Democrat Mary Peltola's campaign had recruited him to run, as we reported Wednesday.

A CBS crew in Petersburg found no sign of an active campaign, including outside his home, and dozens of residents said they never received any campaign material from him. A friend said he and his wife are known for traveling the world. Residents were split: one supporter told CBS that Sullivan is the only candidate who can represent Southeast Alaska, while fisherman Andrew Worhatch said, "I don't think it's a serious candidacy."

Sullivan didn't respond when Petersburg public radio station KFSK sought comment Wednesday, and CBS's report carries no comment from him. He has said his campaign had no connection to Peltola's.

Michael Heyman, the U.S. attorney for Alaska, said Friday that the reporting on the candidate's origins was "troubling" and had prompted a "significant surge of law enforcement assets" into the state, though he wouldn't say which crimes prosecutors are weighing, according to CBS. Heyman said the matter had been "going on sort of quietly for several months." He had been recused while under consideration for a judicial nomination, and that recusal "has officially been rescinded," he said.

The Justice Department, which has subpoenaed several Democratic officials, will seek a preliminary injunction and expedited discovery by Monday in its civil suit to stop Alaska from certifying the result if Sen. Sullivan loses because of voter confusion, Heyman said. The administration filed that suit last week, as we reported, and Todd Blanche defended it in a testy exchange with CNN's Dana Bash.

Gov. Mike Dunleavy has ordered a separate state investigation into whether Peltola's campaign should face criminal charges or civil penalties, and said the state could stop or change certification of the Senate result if it finds illegal conduct. Peltola has said she "knew nothing about" the Petersburg candidate and is "not interested in tricking voters." No one has been charged.

State election officials struck Daniel J. Sullivan from the ballot earlier this year, citing a "deliberate attempt" to confuse voters, but a judge put him back on. He then finished third in the August top-four primary to advance to the general election, Alaska Public Media reported. Sen. Sullivan calls him a "sham candidate."