The source said investigators were not sure of the significance of the names and did not know if it was a list of people Hodgkinson was targeting.
'Congressman Steve Scalise is in serious condition.
The doctors said that while Scalise remains in critical condition, they "are encouraged by improvement in his condition".
The rifle-wielding 66-year-old, who died during the attack, had a history of anger aimed at Republican officials.
Mika, a MI native, was one of five people shot when a gunman opened fire Wednesday as the Republican team practiced in Alexandria, Virginia.
Sava said Scalise will require surgeries soon for abdominal and bone injuries, in addition to the two he has undergone to fix a bone in his leg broken by the bullet.
Scalise, the No. 3 House Republican, arrived at the hospital via helicopter in shock, with intense internal bleeding, Sava said.
"The congressman's status remains critical", Dr. Jack Sava, the director of trauma at the MedStar Washington Hospital Centre, told reporters on Friday. The round fragmented and did substantial damage to bones, internal organs and blood vessels.
Because the bullet shattered, there may be hundreds of fragments in Scalise's body and doctors do not intend to try to remove them all, Sava said.
The Republicans had been holding early morning practices for weeks at the Alexandria, Va., field for the annual baseball game on Thursday against Democratic lawmakers.
Griner remained in the hospital in good condition after sustaining a gunshot wound to the ankle, according to a Friday update.
He said that Scalise has been mostly sedated but they've been able to turn down his medication enough for him to respond to family members.
Sava said that after being released from the hospital, Scalise "will require a period of healing and rehabilitation".
In that awful crime, the country also witnessed the incredible heroism of the Capitol Police, he said, adding that Special Agent Crystal Griner - who he also met during his visit to the hospital - raced into gunfire, along with Special Agent David Bailey.
At Friday's hospital news conference, Scalise's chief of staff Brett Horton read a statement from Jennifer Scalise, the congressman's wife.