_______________________Democrats in the U.S. Senate have gathered enough votes to block a resolution opposing the Iran nuclear agreement. This means President Barack Obama will not have to veto such a measure -- a significant political victory for him. _______________________美国参议院民主党议员已收集到足够的支持投票来阻止反对伊朗核协定的决议.这意味着奥巴马总统将无需动用否决权-这对他来说是政治上的一次重大胜利.