For most emerging young actresses, the titular role in “Juno” — Jason Reitman’s bittersweet comedy about an aphorism-spouting, Dario Argento-worshipping, preternaturally self-aware teenage mother-to-be — would be an estimable chance to show some range.

But in the case of 20-year-old Page, who first attracted attention as the Dolores Haze/Paul Kersey hybrid in “Hard Candy” and later courted multiplexes in the guise of a teenage mutant in “X-Men: The Final Stand,” it’s her most down-to-earth role to date, and arguably her best perf.

It’s also Page’s first comedic lead, though the thesp hardly seems daunted by the transition.

“It was one of the best scripts I’ve ever read,” Page says. “Yes, it’s a comedy, which comes along with certain preconceived ideas, but to me it was just extremely genuine, which is what’s most important to me.

“I think with a comedy, it’s easy to approach it in a way that would lead it to feel contrived or forced,” she continues. “Regardless of the genre, a film should be sincere and honest, or else there’s be a lack of connection on an emotional level.”

Judging from the deafening buzz that materialized around “Juno’s” preem at Toronto and quickly drifted southward, Page has had little trouble connecting.