A couple of weeks back, I says to the prime minister, I says, “C’mon Stevie, lighten up! Turn that frown upside down!”

Son of a gun, he did.

Move over, old, grey, aloof Stephen Harper. Hello, Stevie Wonder!

Check out the video that mysteriously hit YouTube near midnight Tuesday. Someone shot it during what appears to be a rehearsal for Harper’s speech on election night in 2011.

The great Canadian aper Rich Little has nothing on our prime minister.

“I do ‘em all,” says PM Stevie Harper on the video. And he does. His versions of predecessors John Diefenbaker and Joe Clark are hysterical.

Mimicking Clark’s robotic arm gestures, he intones, “We will govern as if we have a majority!”

The twist, of course, is that Clark’s minority government fell in mere months, while Harper that night would win, finally, his coveted majority.

Stevie also does killer impressions of barrel-voiced predecessor Brian Mulroney and squeaky Reform pioneer Preston Manning.

All the while wife Laureen tells him to get serious and son Ben, then 15, rolls his eyes like my own kid does when I crack corny jokes.

“Read the speech, dad,” Ben says, “read your speech, jeez!”

Finally, he grins and gives up. “You’re just too clever, dad.”

Just too clever is right, whoever posted this video in the midst of the Senate scandals and Trudeaumania 2. Brilliant.

I bet that video is worth 100 times its weight in attack ads. The most stone-hearted socialist might vote for that playful guy on the screen.

Someone named “Steve Harper” uploaded it, but I have a hunch the PM wasn’t playing around on YouTube Tuesday night. I assume the video is real. I don’t see any Somalian drug dealers or Toronto Star reporters.

But never mind my cynicism about the timing of the “leak.” The content rings true. When the video was shot, the Senate scandal was barely a twinkle in Mike Duffy’s eye.

Besides, you could have a beer and poutine with this YouTube prime minister.

Stephen Harper, warm and playful? Who knew?

Sure, he has shown signs, notably a priceless bit pretending Rick Mercer was sleeping over at 24 Sussex.

“When I can’t sleep, I count ridings,” the PM told a tucked-in Mercer.

Harper also let down his hair — if that is physically possible — on the series Corner Gas, deadpanning at a mock prairie scrum:

“Now, I like prairie dogs and I like gophers, but sadly neither were given the respect they deserve under the previous Liberal government.”

Mind you, everyone guested on that show, including previous Liberal prime minister Paul Martin.

Harper also showed his musical side, at the National Arts Centre, accompanied by iconic cellist Yo-Yo Ma. The PM played piano and crooned the Beatles’ With a Little Help From My Friends in a surprisingly high voice.

Now we know he was doing his singing impression of Preston Manning.

But such frivolities are few and far between. Generally, Harper seems as drab and dry as, say, an economist, which is what he was before we made him prime minister.

That seems odd, since the U.K. study I quoted last month found fellas named Steve were the most mirthful.

The new YouTube video proves it.

Give us more, Stevie!

Let’s see you do Justin Trudeau.