By Elise Viebeck - 02/07/13 08:48 PM EST
All are critics of the Affordable Care Act, like Christie, but say the policy will not necessarily threaten state budgets.
Under the healthcare law, the federal government will cover all initial costs for adding new Medicaid beneficiaries, then scale back its contribution to 90 percent over time.
Pressure has been growing on Christie to support the expansion, a decision the New Jersey legislature would support. He is slated to present the state's new budget on Feb. 26.
Reps. Frank Pallone, Bill Pascrell, Rush Holt, Albio Sires, Donald Payne Jr. and Robert Andrews also signed Thursday's letter.