Blake Shelton Sings at Surprise Holiday Benefit with the USO

Country music fans still have a chance to sing with a country star for the holidays.

Blake Shelton surprised fans with a semi-impromptu event with the USO Show Troupe last week.

JCPenney sponsored a portion of the event on Thursday, December 19th at Greely Square park in New York City with virtual carolers and 3D projection mapping over the Manhattan Mall.

The retailer was promoting another event called the "Jingle Mingle," which allows fans to sing "Silent Night" with the Grammy nominated singer by uploading videos to  jcp.com/jinglemingle.  Videos can be watched online through December 31, 2013.

For every jingle uploaded JCPenney will donate $20, up to $100,000, to United Service Organizations, Inc. for support of troops and their families.