washington republican tax bill u.s. senate stall procedural problem late thursday force lawmakers weigh new options amendment seek lead fiscal hawk address project large expansion federal deficit measure senators say senator bob corker want add provision bill would trigger automatic tax increase years ahead tax cut bill fail boost economy generate revenues sufficient offset deficit expansion senate parliamentarian bar corker trigger proposal get realization parliamentarian probably go work say republican senator david perdue response republicans consider build future tax increase bill threshold anymore tax increase ... thing come table trigger concept perdue say republican tax bill stumble deficit 'trigger new options weigh