Massachusetts Sen. John Kerry yesterday said he doesn't think Don Imus should have been fired for his racially charged comments - a sharp break with the current Democratic 2008 front-runners. "You know, the punishment has to fit the crime, so to speak," Kerry, the Democrats' defeated 2004 White House hopeful, told NY1. Kerry, who had Imus' support in that race, said he might be willing to go on a future Imus show if the radio host finds a new station - but "if he goes back to doing the same old, same old, I'd have trouble doing that."