Anti-Mormon attacks on Romney

Last Thursday, news broke of anti-mormon calls being made in New Hampshire and Iowa. These were essentially attacks on Romney. Every other campaign has denounced the attacks and denied any involvement. McCain has gone as far as to ask the New Hampshire Attorney General to investigate. The latest speculation is that Romney may be behind the calls so that he can innoculate himself against attacks on his faith (similar to how Kennedy was behind anti-Catholic calls in 1960). An article detailing the possible links to Romney is here.

I'm curious as to the advisability of this tactic (whether it is by Romney or someone else). Presidential elections are open to much scrutiny, so I expect that we will learn who was behind the calls sometime soon. If it was Romney, will this actually help him? Or was it a political miscalculation that will dilute his leads in New Hampshire and Iowa?