By Elise Viebeck - 11/16/12 05:54 PM EST
"The time has come for you to ... act on behalf of the people of New Jersey," he wrote with New Jersey Sens. Frank Lautenberg (D) and Robert Menendez (D).
"Further delay in signing this legation threatens New Jerseyans' access to the best quality and most affordable health insurance."
According to a review by The Hill, 17 states and Washington, D.C., were committed to building their own marketplaces as of Thursday night. Twenty have said no to running their exchanges, and another five said they are planning to partner with the federal government.
Eight, including New Jersey, were undecided.
Healthcare experts agree that state-run exchanges will operate better than those run by the Health and Human Services (HHS) Department.
HHS has now extended deadlines related to the exchanges twice as it works to encourage states to implement their own using billions of dollars in federal money.