Had a good Republican run, Lieberman would have run a different campaign (emphasizing his liberalism even more) and taken some of the 39% that Lamont got; also, increased GOP turnout with a good candidate running instead of a card-counter who was condemned by the party would have increased the denominator and thus make that 39% closer to 35%. The Republican could have won with 35% or 36%, unless either Lamont or Lieberman cometely collapsed into the 20s.
finally, somebody cracked the Leebaman code.