OTTAWA - Prime Minister Stephen Harper didn't bother speaking to his party's annual Christmas gala -- he sang to them instead.

And unlike the last time when Harper tickled the ivories with a solitary Beatles tune, this time he rocked the party.

From Neil Diamond's "Sweet Caroline" to The Proclaimers' "I'm On My Way," Harper had hundreds of parliamentarians and staffers dancing and clapping in a packed downtown Ottawa ballroom on Wednesday night.

He even left the piano behind for one song, criss-crossing the stage with an energetic version of The Who's "The Seeker," before closing up the Guess Who's "Share the Land."

For an encore, the prime minister belted out the Rolling Stones' "Jumpin' Jack Flash."

But he didn't leave his beloved Beatles behind, taking a minute for a quiet piano tribute to John Lennon on the 30th anniversary of the rock icon's death.

Harper first took to the stage in public last year at a black tie National Arts Centre gala, where he surprised the crowd by striding out to play the Beatles "With a Little Help from my Friends," backed by cellist Yo Yo Ma.

His performance came a year after he had dismissed galas as the playgrounds of the elite, and his star turn was credited by many as helping him both overcome that remark and brighten up his staid image.

Three months later, he made the extraordinarily unpopular move of proroguing Parliament.

As the Commons prepares to end this fall session, Tory party insiders are feeling generally optimistic.

Harper noted to his caucus on Wednesday morning that their government has now surpassed Lester B. Pearson's for the longest amount of time in a minority position without a confidence vote.

Still, the upcoming budget has some worried that the party's gently rising poll numbers could be at risk.

"Everyone tells me you want to hear another song," Harper joked as he took the stage on Wednesday night, dressed in a untucked black shirt and pants.

Despite the jovial atmosphere among partygoers on Wednesday, Harper didn't stay long.

After wild applause for his encore, he bowed, gave a little wave and it was exit stage left.

Said the master of ceremonies: "ladies and gentlemen, the PM has left the building."