The Obama administration on Tuesday starkly warned Republicans against a "repeal-and-delay" strategy on Obamacare as it announced that more than 11.5 million Americans have signed up for health insurance coverage on government-run marketplaces this enrollment season — a slight increase from last year. Administration officials, citing previous third-party analysis, said 30 million people could lose coverage and individual health plan prices could spike dramatically if Republicans voted to repeal key parts of Obamacare but delayed the repeal for several years to give them time to craft a replacement.

"It's important to remember that repeal-and-delay ultimately means gambling on millions of people's health care on the assumption Congress will pass a replacement plan," said Benjamin Wakana, spokesman for U.S. Health and Human Services Department Secretary Sylvia Burwell. "The stakes are too high on moving forward with repeal and not knowing what comes next yet," Wakana said. Wakana's warning came as Obamacare enrollment for 2017 headed into the home stretch, and as GOP leaders in Congress struggled over the question of whether to repeal major parts of the health-care reform law without a replacement plan in place, or repeal and replace at the same time. It also came as the Council of Economic Advisers released a brief that concluded that big price hikes in Obamacare plans for 2017 appear to be "a one-time correction." That brief also found that those premium increases are not substantially harming either enrollment in the individual insurance plan market, or that market's "risk pool," its mix of healthier and sicker customers whose premium payments and benefits usage offset one another.