The San Francisco 49ers potentially could see multiple coaches emerge as NFL head-coaching candidates this month.A league source said some teams (there are currently six teams without a head coach) are beginning to do background work on defensive line coach Jim Tomsula. He could emerge as a candidate in the next week. As per league rule, coaches in the wild-card round (the 49ers play at Green Bay on Sunday) can't interview this week.Tomsula could be considered a long-shot because he's never been a NFL coordinator.