In fact, it's hard to unravel where Finch ends and Radcliffe begins, so thoroughly do the two seem to be entwined in this triumphant performance. On the surface, the British actor — with his squat, compact body and somewhat pasty complexion — seems an unlikely leading man. Though he has a stronger singing voice than Broderick and a limber, go-for-it approach to director Rob Ashford's exhaustingly acrobatic choreography, he's not a natural, effortless triple threat. But like Finch, he seems to be tapping into an almost bottomless reserve of willpower and determination to claim his place in the spotlight of a big-budget Broadway musical. Your eyes keep being drawn to him, even if he always lets you see him sweat.

And he certainly works up a sweat on some of the most athletic production numbers I've seen on stage in years, particularly the football-themed ''Grand Old Ivy'' and the Act 2 showstopper ''Brotherhood of Man.'' The latter places Radcliffe front and center as the well-toned ensemble leaps, thrusts, spins, and stretches with joyous abandon — all while singing one of Loesser's catchiest melodies. I wished I had a remote control to replay the entire song from the top. Over and over again.