Obama, D-Ill., edges McCain, R-Ariz., by 43 percent to 41 percent among likely Michigan voters asked, well within the four-point margin of error in the Detroit News-WXYZ Action News poll. Some 12 percent of respondents said they were still undecided, while 5 percent chose third-party candidates Bob Barr or Ralph Nader, the Detroit News said Tuesday.

"Just as we thought, it's going to be a close race in Michigan," said David Dulio, a political science professor at Oakland University.

The survey was more positive for McCain than other recent polls. Real Clear Politics, a national political polling Web site, shows Obama leading by a 7.7-point margin in Michigan.