The widespread enthusiasm that swept Barack Obama into office two years ago has evaporated and many of the voters who once bought into his brand of change are switching sides. According to a new Associated Press poll, a quarter of the people who voted for him in 2008 will be or are considering casting their vote in favor of a GOP candidate this November, while about half of them reported they would stay home. That said, around the same number of people who supported John McCain in 2008 said they were supporting Democrats this fall or still on the fence. Two-thirds of those McCain supporters, however, said they would definitely vote and that enthusiasm gap is largely responsible for the Democrats’ struggles in the polls. Obama has undertaken a wide-ranging “get out the vote” operation in the final weeks of the campaign in an effort to assuage disappointed voters.