The Northwestern Wildcats turned a successful 2012 campaign into a 19-player (21 counting walk-ons) National Signing Day class on Wednesday.

After capping their season off with a win over the Mississippi State Bulldogs in the Gator Bowl, Northwestern finished 10-3 overall (5-3 in the Big Ten), good for third in the conference's Legends division. On Wednesday, the Wildcats signed 15 three-star prospects, according to Rivals, with the day's highlight coming when they landed four-star quarterback Matt Alviti from Park Ridge, Ill. Along with Alviti, the Wildcats signed five players from the state of Illinois.

SB Nation's complete coverage of National Signing Day

Alviti is listed as a dual-threat quarterback, and is the 11th-best prospect in the country at the position. In 2012, sophomore Trevor Siemian and junior Kain Colter split time as Northwestern's signal-caller.

SB Nation's National Signing Day coverage

One of the bigger losses the Wildcats on Signing Day came when four-star wide receiver James Clark chose to sign with the Ohio State Buckeyes. Other than that, as SB Nation's Sippin' on Purple writes, the day went pretty much according to plan for Northwestern.

Here's Northwestern's roundup of their signees, complete with summary capsules and video highlights for each prospect.