The Boss is mocking his biggest fan.

New Jersey rocker Bruce Springsteen appeared on Tuesday's episode of "Late Night with Jimmy Fallon," singing about the bridge scandal engulfing Gov. Chris Christie.

Springsteen and Fallon - wearing matching shades, bandanas and denim cut-off shirts - sang about the September George Washington Bridge backups in a song called "Gov. Christie's Fort Lee, New Jersey Traffic Jam," set to Springsteen's hit "Born to Run."

The traffic jams were linked to a top Christie aide in emails released last week, supposedly a dose of political payback against Fort Lee's Democratic mayor. Christie apologized for the closures in a two-hour press conference Thursday.

In "Traffic Jam," Springsteen poked fun at the length of Christie's speech, singing that it was longer than one of his concerts.

Christie would know; he has attended plenty of Springsteen's shows. But the two remain politically divergent, a rift reaffirmed by the Boss' song.