American Idol runner-up Katharine McPhee is engaged to actor Nick Cokas, sources tell PEOPLE. McPhee, 23, recently has been showing off a ring from Cokas, 42. They have been dating for more than a year.

"Katharine is bubbling over with excitement for her upcoming wedding," a source says. "She is all smiles when she talks about the planning. It sounds like everything is going very smoothly."

Once she realizes he's gonna need Viagra to keep that cock going in the next couple years, she'll be runnin' for the hills.

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