Michigan head coach Jim Harbaugh contacted 2016 four-star quarterback KJ Costello (Rancho Santa Margarita, California) on Monday night, according to Wolverine 247's Steve Lorenz.
Costello currently holds an offer from Michigan that was extended to him by former offensive coordinator Doug Nussmeier. There was a ton of mutual interest between both U-M and Costello and the commitment of fellow four-star Messiah deWeaver has not changed that.
Harbaugh took multiple quarterbacks in every recruiting class at Stanford except for the year they brought in Andrew Luck. Look for something similar to that at Michigan.