Josh Groban is the Justin Bieber for middle-aged housewives and gray-haired grandmas — only he can really sing.

Really, really sing. And play the piano, tell jokes, think on his feet and just flat out entertain. For instance, on Saturday at Target Center, he did his Bieber impression, singing “baby baby baby” in his beliebable voice and saying “I’m-a-marry-you, girl.” OK, Justin may break more hearts than Josh did — older women might dream, but they don’t scream — but Groban has a career that will last.

Six studio albums into his 12-year recording life, the 32-year-old has undertaken his first in-the-round tour and he pulled it off effortlessly and effectively. He was poperific.

The popera star had a smart balance between his so-called classical crossover tunes and plain old pop tunes all Groban-ized. For 95 minutes, he turned on his endless charm, whether it was his self-deprecating humor, well-schooled references about the Twin Cities (he said he’s been here 25 times, mostly to write songs with Dan Wilson) or engaging casualness of a plain white T, sport jacket and 3-day beard.

His unpretentious patter and let’s-get-goofy demeanor offset the syrupy richness of his repertoire. You may not know what those Italian or Spanish lyrics mean, but the melodrama and romance of Groban’s performance clearly translated. Nearly every song that he’s made famous — from the recent single “Brave” to the closing “You Raise Me Up” — turned into a bravura ballad of monumental inspiration.

But what probably made this Groban’s most satisfying Twin Cities show was that there were many songs on which his operatic baritone didn’t explode like an aspiring vocalist on “American Idol.” “To Where You Are” showcased savvy dynamics and vocal restraint. Jimmy Webb’s “The Moon Is a Harsh Mistress,” just voice and piano, was a flawless straight-ahead ballad. Don McLean’s “Vincent” was pretty and understated, with moody purple lighting. (All night long, the lighting was dark and artful, maybe too much so at times.)

But many of the 7,500 (mostly female) fans probably came to hear Groban unleash that magnificent voice of his. And, of course, he accommodated them. “You Raise Me Up” felt like the Grobanian national anthem with everyone standing, and he even did his epic “The Prayer” with opening act, Judith Hill of NBC’s “The Voice” fame, taking the Celine Dion part. Even though Hill was quite impressive in her own set, it felt like a welterweight singing with a heavyweight on “The Prayer” because her voice, though big and true, wasn’t thick enough to hold its own with Groban’s.

He may have found himself another singalong uplift with his new single, Stevie Wonder’s “I Believe (When We Fall in Love It Will Be Forever),” which was predictably volcanic and bolstered by the harmonies of the Twin Cities’ own Choral Essence. Maybe that tune has supplanted “Believe,” his big hit from “Polar Express” that he didn’t do — to the objections of the guy (yes, a guy) behind me.

But Groban, like Bieber, knows who are the true ­believers in his audience.