Romney won the debate last night according to immediate polls, but the actual effect is unclear on the number of undecided voters he actually turned. There was a set of 39 undecided voters on a panel and only 16 of them said they would vote for one of the two candidates and it was split equally 8 and 8 between the two. An additional problem is that Romney straight up lied through his teeth last night and is going to get nailed for the next two weeks about it by fact checkers.
Obama looked sleepy and talked professorially and therefore "lost" the debate because he seemed like he didn't have enough energy to fight back, but policy-wise he didn't stretch the truth nearly as much as Mitt.