Phillips, the fifth consecutive male "Idol" winner, was the favorite going into the finale, after managing to stay out of the bottom three the whole season.
Phillips, who got the majority of the 132 million votes cast in his finale showdown with runner-up Jessica Sanchez, suffered health problems throughout the competition, including a serious kidney problem that will necessitate surgery before he embarks on the annual "American Idol" summer tour.
Meanwhile, another "Idol" pair almost stole the show.
Host Ryan Seacrest pulled Young (a season five alum) and DeGarmo (a season three alum) on stage, setting the scene for Young to make his proposal.
"This has always been home to us and I felt that this would be the perfect place to ask a simple question," Young said. "Diana, we have conquered Broadway together. We have created all your new music together. We have an amazing group of people around us.
"I love you to death, you're my best friend, I wanna make this last forever," he added, getting down on one knee before asking her if she'd marry him.
She said yes, they kissed, and she got a look at the ring. "Wow, babe, you picked a good one," DeGarmo said. "My makeup's running!"
"Mine, too, after that," Seacrest quipped.
