“I would anticipate that this will help Obama’s case with what has been his weakest area lately — working-class white voters,” Dave Redlawsk told Iowa Independent when he learned of John Edwards’ anticipated endorsement of Barack Obama. Redlawsk is both a University of Iowa political science professor and a national delegate for Edwards.

Several sources reported Wednesday afternoon that Edwards is expected to endorse Obama tonight at a Grand Rapids, Mich., joint appearance.

“At the same time, it probably makes no real difference at this point in the primary campaign,” Redlawsk added. “I would expect Edwards to campaign actively for whoever was the nominee in any case.”The Michigan site is significant, as both Obama and Edwards took their names off the Jan. 15 Michigan primary ballot because the state violated party scheduling rules. Obama has been making Michigan visits in recent days as he tries to work through the issue of seating the state’s delegates — an issue Hillary Clinton repeatedly raises. (Our sister site, Michigan Messenger, liveblogged the event.)

Last Friday, Edwards was grilled at length on MSNBC’s “Morning Joe” program and said he would endorse the candidate he had voted for in the May 6 primary in his home state of North Carolina. Edwards repeatedly evaded the question of who he had voted for, but near the end of the interview appeared to say, “I just voted for him this week.” He later denied he had said “him,” saying the syllable was an “‘em.” But it clearly was not a “her.”

Edwards joins fellow former candidates Chris Dodd and Bill Richardson in endorsing Obama. Joe Biden and Dennis Kucinich have not yet endorsed, while Mike Gravel has (1) endorsed a Green candidate; (2) changed his affiliation to Libertarian, and (3) continues to appear on Democratic primary ballots.