District Council 37—the city's largest union which represents municipal workers—threw its support behind City Comptroller William Thompon's mayoral bid yesterday. On why Mayor Michael Bloomberg, who won the endorsement in 2005, lost out, DC 37 executive director Lillian Roberts noted, "He's changed! He's changed!"—the union was also unhappy the mayor directed $9 billion of city work to outside contractors (which the mayor said saved money). And Local 2627 president Robert Ajaye said of Bloomberg, "He's arrogant, too arrogant." Bloomberg's reaction was, "I will not make irresponsible promises to win an endorsement," (he did promise 4% raises in 2005, but times were so different then!). The NY Times, which says it's an "unexpected boost" to Thompson, has analysis: Regarding the DC37 and Working Families Party endorsements of Thompson, "the groups indicated that they had soured on the mayor because of what they felt were an imperfect feel for the city’s working class and his imperious move to rip up the city’s term-limits laws in order to run for another term."