WASHINGTON — President Obama's reelection and Democratic gains in Congress were supposed to make it easier for the party to strike a deal with Republicans to resolve the year-end fiscal crisis by providing new leverage.
But they could also make it harder as empowered Democrats, including some elected on liberal platforms, resist significant changes in entitlement programs like Social Security and Medicare.
As Congress returned Monday, the debate over those programs, which many Democrats see as the core of the party's identity, was shaping up as the Democratic version of the higher-profile struggle among Republicans over taxes. In failed deficit-reduction talks last year, Obama signaled a willingness to consider substantial changes in the social safety net, including a gradual increase in the eligibility age for Medicare and limits in the growth rate of future Social Security benefits. An urgent question hanging over the new round of deficit talks is which of those changes Obama and congressional Democrats would accept today.
While a potential change in calculating Social Security increases was part of the talks with Speaker John A. Boehner last year, the White House press secretary, Jay Carney, made clear Monday that the administration was not considering changes to the retirement program as part of the deficit talks.
''We should address the drivers of the deficit, and Social Security is not currently a driver of the deficit,'' Carney said.
Republicans insist that changes in the major entitlement programs be on the table in exchange for their willingness to accept increases in tax revenue.
But Democrats have given no indication that they are willing to consider policy changes or savings of the magnitude demanded by Republicans.
The underlying dispute highlights a reason the politics of the deficit are so thorny: Even as many voters say they want Washington to reduce the budget deficit, they oppose many of the benefit cuts and tax increases that could help achieve that goal.
As the negotiations enter a more crucial phase, influential outside advocacy groups like AARP and the National Committee to Preserve Social Security and Medicare are weighing in, alerting their members to possible changes in the popular programs. In the current negotiations with Congress over deficits and the debt, Obama said he would take a serious look at how to ''reform our entitlements'' because ''health care costs continue to be the biggest driver of our deficits.'' Unless Obama and Congress reach some agreement, tax increases and budget reductions will take effect automatically Jan. 1.
Obama's room for maneuvering is limited by several political factors. In the presidential campaign, for example, he attacked cost-cutting proposals by his Republican opponents and won support from millions of voters by promising to defend Medicare.
Moreover, since the Supreme Court upheld the new health care law in June, Obama has become skittish about cutbacks in Medicaid, the federal-state program for low-income people.
The court said the expansion of Medicaid was an option for states but not a requirement. Cutting federal Medicaid payments to states could reduce the federal budget deficit but could also cripple Obama's efforts to persuade governors to expand the program, the foundation of his health care overhaul.
Even if Obama and Republican leaders in Congress could agree on savings in Medicare and Medicaid, the president would face resistance from some liberal members of his party who oppose cuts in the two giant health care entitlement programs.