Someone tell the people at Colbert Nation to tell Stephen Colbert to pressure the Cubs to let him sing the national anthem* at Wrigley, since he did attend one of our finest institutions of higher education and studied under Del Close at Second City. Yes We Can! (h/t Liz; unfortunately, this isn't quite as good as the four-part-harmony version with Colbert, Carell, Samantha Bee, and Rob Corddry, but as far as I know that's only on the Indecision 2004 set; see also Colbert with John Legend)
*One of the things I love about this country is that we ended up with an exceedingly difficult-to-sing (it covers a range of one-and-a-half octaves**) national anthem, despite the existence of more facile alternatives*** such as "America the Beautiful" and Lee Greenwood's "God Bless the USA." But it's a feature, not a bug: when someone screws it up they really screw it up, which is always entertaining; alternately, when someone nails a rendition, either traditional (Whitney Houston, and I gotta admit I like the Dead's version) or innovative (Marvin Gaye), it's thrilling. "The Star-Spangled Banner" demands you come to play, which is resonant.
***Garrison Keillor insists that it wouldn't be so hard if we moved the key back to G where it belongs.