Why? A look at the states that benefit the most from the tax break helps explain it — they are all Democratic strongholds, or so-called blue states. Proposals by House Republican leaders and President Donald Trump would repeal the tax break as part of their packages to overhaul the American tax code. The standoff illustrates how hard it is for Congress to eliminate any popular tax break, even one that primarily benefits the ruling party's political opponents. The deduction allows taxpayers to write off real estate taxes, and state and local income taxes. Rep.