Lori Montgomery at the WaPo:
.... On Dec. 31, the George W. Bush-era tax cuts are scheduled to expire, raising rates on investment income, estates and gifts, and earnings at all levels. Overnight, the marriage penalty for joint filers will spring back to life, the value of the child credit will drop from $1,000 to $500, and the rate everyone pays on the first $8,700 of wages will jump from 10 percent to 15 percent.
The Social Security payroll tax will pop back up to 6.2 percent from 4.2 percent under the deal approved Friday by Congress. And new Medicare taxes enacted as part of President Obama’s health-care initiative will for the first time strike high-income households.
The potential shock to the nation’s pocketbook is so enormous, congressional aides have dubbed it “Taxmageddon.”
Since they took control of the House last year, congressional Republicans have needed nothing from Obama. They were the holdouts, demanding big cuts in federal spending in exchange for helping Obama keep the government open and raise the legal limit on government borrowing, known as the debt ceiling.
But in December, deadlock will cut the other way. Republicans need Obama if they want to prevent one of the biggest tax increases in U.S. history — nearly $5 trillion over the next decade, by official estimates — and block deep cuts to the Pentagon that could be triggered as part of last summer’s debt-ceiling accord.
The tax shock is set to occur after the Nov. 6 election but before the new Congress — and potentially a new president — take office two months later. While the outcome of the contest is likely to color the tax debate, Obama will either be freshly reelected or on his way out and, therefore, free to play hardball with Congress....