State GOP officials say there might be an election challenge by Phillips' opponent, Roger Crowder of Louisville.
Crowder sent the state party a letter saying he wants to keep his legal options open.
Certified results show Phillips won by 448 votes with 69,246 votes cast in the runoff. It's one of the closest statewide elections in recent history.
Phillips will face two-term Democratic incumbent Lester Spell in the November 4 general election.