"I've got two small children and it's hard enough to get to spend a lot of good quality time now. I have a wife. They are all very important to me and at the end of the day family has to be number one,'' he told the St. Petersburg Times.
"I come at this from a different place than a lot of members. This decision, it wasn't an easy decision,'' said Mack.
A February Mason-Dixon poll showed Nelson leading Mack by only 45%-40%.