With Congress on the verge of imposing a new tax on high-cost health insurance plans, skeptics continue to raise questions about who would be hit hardest and whether healthcare spending would be limited as much as proponents say, the Washington Post reports. The Senate healthcare legislation includes a 40% excise tax on insurance plans worth more than $23,000 per year for a family of four. When the legislation would go into effect in 2014, only a small fraction of all plans would be taxed, but more would be captured over time. The House legislation relies on an income tax surcharge on families earning more than $1 million. But some Senate Democrats are opposed to the surcharge, and the excise tax has been endorsed by the White House and many healthcare economists, the Post reports.