Republicans currently control Congress by slim margins, raising the stakes if voters who lose their ACA tax credits blame them at the ballot box. Catastrophic plans are a little-known type of Obamacare policy that have previously been limited mainly to people under age 30. AHIP, the insurance industry lobbying group, is pushing hard for the larger tax credits to be extended. People who choose catastrophic plans are not eligible for any ACA tax subsidies to help pay monthly premiums. Keith said the ruling was a “bigger deal” than expanding eligibility for catastrophic plans.