The pairing of Lalah Hathaway and Ruben Studdard is a marriage made in R&B heaven.

Both have special voices, she a rich milkshake-like contralto with quite a bit of range, he a robust tenor with power to make heaven and earth move. When you hear him live, there's no doubt that America got it right (sorry Clay Aiken) when voting him "American Idol" in 2003. And, live, Hathaway is clearly her father's daughter, a genre blender who oozes intimacy and soul.

But what was apparent Sunday at the Hathaway/Studdard joint performance at the Dakota Jazz Club is that these two great singers are, like many other great singers, in search of great songs. The 85-minute second set was filled with mostly covers of famous tunes.

That's not to say that it wasn't a special evening – because it was. They opened with the old Roberta Flack/Donny Hathaway hit, "Where Is the Love," and closed with a joyous version of Michael Jackson's "Rock with You" that eventually evolved into a medley of Michael hits, complete with Lalah singing some of the introductions of the band members and a pitch for CD and autographs after the show.

During the seamless program, each of the stars had solo segments as well as collaborations. Lalah sparkled on "Summertime" and Luther Vandross' "Forever, For Always, For Love," which had women swooning to Lalah's sexy cooing and Adam Hawley's bluesy/jazzy guitar solo. (Lalah had scored R&B hits with versions of both of those classics.) And her scat singing was the perfect exclamation point for the groovy, Grammy-winning "Something."

Studdard did his biggest hits, "Flying without Wings" and "Sorry 2004," and stood out on a killer medley of Vandross nuggets, peaking with the deliciously dramatic "Superstar," as Ruben was killing the audience softly with his song.

To close the main set, the strikingly thinner Studdard, 35, who is tall and bald, and Hathaway, 45, who is short with long braids, teamed up for a reading of the Marvin Gaye/Tammi Terrell hit "If This World Were Mine," with both singers dragging out their phrasing to add extra layers of emotion.

The affable stars were quick on their feet, with quips often coming In mid-song such as Studdard asking how many people voted for him on "Idol" or, after one man declaring to Hathaway that "I done fell in love now," she shifted into a deep whisper and shouted playfully: "Security."

Hathaway and Studdard will perform again at 7 and 9 p.m. Monday and Tuesday at the Dakota.

Photo of Ruben STuddard by LeAnn Mueller.