TRENTON, NJ (TIP): Gov. Phil Murphy is opposed to a broad tax cut plan for New Jersey’s seniors being pushed by a top state lawmaker and is willing to shut down the state government over the proposal, NJ Advance Media has learned. Murphy would veto the proposal if it’s sent to his desk as is, over concerns that it’s “irresponsible” because it would benefit even the richest residents 65 and older, as well as worries over how the state would pay for it at a time when tax revenue is dropping, according to two senior administration sources.The sources spoke on the condition of anonymity because they are not authorized to discuss the matter in public. The development adds a large layer of uncertainty and new drama during the final month of negotiations between Murphy and his fellow Democrats who control the state Legislature as they hammer out a final state budget, due by July 1. If they don’t come to an agreement by the deadline, Murphy could order a shutdown of the state government — something that has happened only twice in state history. The last time was 2017. State Assembly Speaker Craig Coughlin, D-Middlesex, introduced the tax cut plan Monday. Dubbed Stay NJ, it would establish a property tax credit program for all seniors in the Garden State. “It’s time to be there for our seniors, to make our state a better place to retire,” Coughlin, a 65-year-old who recently welcomed his first two grandchildren, wrote in a corresponding op-ed published on NJ.com. State Senate President Nick Scutari, D-Union, said he is working with Coughlin on the measure and suggested the state could help pay for it by extending a corporate business tax surcharge that Murphy and top Democrats have agreed to let expire at the end of the year. But Murphy still plans to let the surtax expire, sources said, despite pushback from progressive advocates and experts who warn against such changes at a time of plummeting revenue and economic uncertainty. The governor is also concerned about the senior tax cut plan because it’s “uncapped,” benefitting even wealthy residents despite seniors already receiving property tax relief from the state, according to the sources. Murphy’s administration is preparing a “contingency” plan for a government shutdown if lawmakers stand firm on the proposal, sources said. That could mean Murphy closes state government services, as well as state parks, just before the July 4 holiday. That’s what happened in 2017, when then-Gov. Chris Christie shut down the government over a budget fight — one that included those famous photos of Christie on the beach. Spokespeople for Coughlin and Scutari did not immediately respond to messages seeking comment Thursday morning.