Jimmy, I'm guessing that you didn't have a tape measure to actually measure the tracks. 4 1/2 inches isn't that big for a Cougar, but would be huge for a Lynx. The final tell for you was the tail tracks in the snow.
We had a big cat cross our property a few years back. I contacted the DNR wildlife specialist in Cloquet, and sent him some pics of the tracks. According to his books a Lynx track should be around 4 inches, and a Cougars should be 5 inches and up.
Without an actual sighting all we could conclude is that it was a monster Lynx, or a young Cougar.
According to the DNR there is no established (breeding) population of Cougars in Minnesota, and the sightings are transient animals. With Cogar sightings on the rise in recent years, many are starting to doubt what the DNR is saying.
Here's a pic of the tracks I found