President Biden’s desire to offset more than $4 trillion in spending proposals with higher taxes is struggling to gain momentum in Congress.

Pockets of skepticism have emerged within Biden’s party over White House plans to raise the corporate tax rate, revamp the international tax system, and double tax rates on wealthy investors, among other measures critical to the administration’s plans.

The party faces regional divides over taxes as well, with farm-state Democrats skittish about taxes on heirs and coastal Democrats demanding the repeal of limits on state and local tax deductions, which would amount to an expensive tax cut that would require higher taxes elsewhere.