Republican leaders have started laying the groundwork to persuade GOP lawmakers to support a compromise on a tax increase, an issue that has deadlocked a congressional "super committee" pressed to come up with a deficit-reduction plan by next week. GOP leaders on Tuesday presented to their rank-and-file members a scenario under which Republicans would agree to $250 billion in new tax revenue over the next 10 years, largely by limiting itemized deductions for upper-income households.