The 27-year-old had seen limited time on the field as a member of the Baltimore Ravens and Arizona Cardinals.
The "seven-figure commitment" provided by West Shore Home and MITER Brands will span over two years.
Clifford threw for 10,661 yards and 86 touchdowns during his Penn State career, and his experience may propel him to a late-round NFL Draft selection.
"He's been invaluable for us."
New members join through competitive auditions, and all members, both new and returning, must audition annually.
The annual Blue-White Game is back along with many fan experiences, including the Blue-White Boardwalk.