But Ryan's victory was marred by controversy over a last-minute effort by Republicans to weaken the independent congressional ethics office, a reminder of the splits within the new Republican majority. Trump blasted Republicans for prioritizing the ethics change, leaving the caucus to reverse itself moments before formally opening the 115th Congress.

Ryan won resounding re-election with 239 votes -- clearing the 218 needed -- with only one Republican voting for someone else. But his relationship with the incoming president will face a test as he carves out his own agenda for Republicans in Congress.

"This is a once-in-a-lifetime opportunity. This is the kind of thing that most of us only dream about. I know -- because I used to dream about it. The people have given us unified government," Ryan told House members after his re-election.