Jon Bon Jovi and his Toronto backers are reassessing whether even to continue in their pursuit of the Buffalo Bills, QMI Agency has learned. Their bid has been on the rocks for weeks and no one within the group is optimistic they'll wind up buying the NFL team, according to two sources in the position to know. The group cancelled a scheduled tour of Ralph Wilson Stadium on Wednesday. "They're hanging on by the skin of their teeth," one source said. "The bid's on life support." It has nothing to do with the announced departure Thursday of CEO Tim Leiweke from Maple Leaf Sports & Entertainment, whose role in the bid has been overstated (most often by Leiweke himself).