OVERSIGHT - ALL ARTICLES
As outside groups pile on, the Republican budget negotiator says he is sticking to principles.
Both sides may have trouble selling the plan.
Bipartisan panel also asks military retirees to sacrifice, spares current workers.
Koskinen promises senators cooperation in probe of tax-exempt division.
If Republicans don't flub the coming fiscal debates like they did in the fall, voters will focus squarely on the health care rollout.