(CBS) The presidential race between Barack Obama and John McCain is now even at 42 percent, according to a new CBS News poll conducted Monday-Wednesday of this week. Twelve percent are undecided according to the poll, and one percent said they wouldn't vote.

This is in contrast to a poll conducted last weekend, where the Obama-Biden ticket led McCain-Palin by eight points, 48 percent to 40 percent.

McCain has also closed the enthusiasm gap some with Obama, but it still exists. Fifty-five percent of Obama's supporters are enthusiastic about their choice, and now so are 35% of McCain's. Last weekend, just 25 percent of McCain's supporters were enthusiastic about him, compared to 67 of Obama's supporters.