"In a Dec. 17 letter to senators, Americans for a Fair Estate Tax said the decision to let the tax expire was 'incomprehensible.' It said the tax’s elimination would be a boost to the wealthy that would negatively affect charitable giving and hurt government coffers.

'Repeal of any weakening of the tax would result in significant loss of revenue for vital public programs and infrastructure, and would benefit only the largest one in 500 estates that are subject to the tax at its current level,' said the group, which includes a number of labor organizations and left-leaning groups.

Only estates larger than $7 million per couple or $3.5 million for individuals are subject to the estate tax.

Democrats warn those under that threshold will be hit by a higher capital gains tax because of Congress’s inaction.

Under the rules set to go into place on Jan. 1, a capital gains tax of 15 percent would apply to estates above $1.3 million. The tax would be calculated based on gains accrued since the estate was purchased.

'The people that are most likely to be hurt by this are the people who have an estate between $1.3 million and $7 million,' said Lee Faris, of United for a Fair Economy, which wants to extend the estate tax."

Read the full article by Ian Swanson in The Hill.