Ms. Wilensky holds out hope that the court might yet prod Congress to act. If a majority of justices call on lawmakers to resolve the ambiguity, she reasoned, Republicans might then salvage the challenged subsidies in return for changes such as curbing health-care mandates on employers.
That may be wishful thinking.
“The kind of changes that Gail is talking about come from a mentality about negotiation between the two parties that used to be the rule here in Washington,” said Henry J. Aaron, a policy analyst at the Brookings Institution who served in Mr. Clinton’s administration.
“People of good will on both sides got together, they didn’t always agree, they worked out their differences and they dealt with problems,” Mr. Aaron said. “That is all too regrettably now missing from the scene here.”