Democrats counter that wealthy households would receive a tax benefit under their plan. The joint committee analysis shows that million-dollar households would continue to receive an average tax break of about $6,300 next year compared with full repeal — significantly more than the average break of about $1,100 that would go to families making less than $200,000 a year, according to the taxation committee.

Despite that bit of news, the nation’s 315,000 millionaires are unlikely to feel grateful; the joint committee said their overall federal tax rate would jump to about 29.9 percent under the Democratic plan, compared with 24.6 percent if all the tax cuts were extended.