WASHINGTON- Former U.S. Secretary of State Hillary Clinton is urging Congress to resist imposing new sanctions on Iran over its nuclear program, saying that 'this is the time' to give diplomacy a chance to work. Clinton, who leads the pack among potential Democratic presidential contenders for 2016, according to Reuters polling, said in a Jan. 26 letter to Democratic Senator Carl Levin, 'Now that serious negotiations are finally under way, we should do everything we can to test whether they can advance a permanent solution.' Her comments came after Levin wrote to her about the sanctions issue. The lawmaker released her letter on Sunday. Fifty-nine of the 100 U.S. senators, including 16 of President Barack Obama's fellow Democrats, co-sponsored a bill that would impose new restrictions on Iran if talks on a permanent deal falter.