But in the Kaiser survey conducted earlier this month, 64 percent said if the court rules that subsidies should be available only in states running their own markets, Congress should make people in all states eligible for federal aid. Those favoring congressional action included 82 percent of Democrats, 40 percent of Republicans and 63 percent of independents.

In addition, 59 percent of those in states whose markets are federally run said their state should create its own marketplace if the court invalidates subsidies in their state. People holding that view included just over 6 in 10 Democrats and independents and about half of Republicans.

People with unfavorable views of the overall law outnumbered those who like it, 46 percent to 40 percent.

Across the country, 9.5 million people have so far signed up for 2015 coverage under the law.