Packed with more live music than perhaps any other political gathering in history, the Democratic National Convention unofficially opened Sunday night with Barack Obama supporter Sheryl Crow changing the words of “A Change Would Do You Good” to “A Change Would Do Us Good” at Red Rocks Amphitheatre outside Denver. Crow, Sugarland and a morose Dave Matthews, grieving after last week’s death of his band’s saxophone player LeRoi Moore, performed acoustic sets for a private “Green Sunday” convention kick-off amid environmental speeches by Robert F. Kennedy Jr., Colorado Gov. Bill Ritter and Virginia Gov. Tim Kaine. Meanwhile, at the Fillmore Auditorium near downtown, a huge, raucous coalition of New Orleans bluesmen and funkateers, including the re-formed Meters and pianist Allen Toussaint, partied until 2 a.m., pleading for assistance to the damaged city’s levees, marshes and swamps. Oscar-winning pianist Randy Newman sat in for two songs, including his eerily Katrina-predicting “Louisiana 1927,” complete with solos from trumpeter Terence Blanchard.