It isn't too much of a surprise, given that three of the four reunited this fall to play a concert for Barack Obama, but the surviving members of the Dead are giving it another go, launching a 19-date tour this spring that stops in Chicago on March 5 with a show at the All State Arena. As with their 2004 reunion shows, Bob Weir, Phil Lesh, Bill Kreutzmann and Mickey Hart will play with Allman Brothers guitarist Warren Haynes and RatDog keyboardist Jeff Chimenti.