I think Christies knows what he is doing. Given Manhattan is based on a small island, NJ doesn't need another tunnel to accommodate the daily commute back and forth to there because Manhattan can't afford more workers.
A project like this will last maybe >10 years. NJ has to make up any shortfall of the budget while federal and NYNJ port authority's downside is capped at $$$ billion. Forgive me, I forget the exact budget numbers.
An additional tunnel won't increase the NJ's real estate value either, because NJ's state tax+ property tax are already ranked #1 throughout the country. Many people fled from the garden state for its high tax. Such tread can not be reverted by another tunnel.
