Still, Moody's analysts were not assuaged.
"Despite the Obama administration's optimism, we continue to have doubts about the enrollment outlook based on the economics of the situation for those not receiving a government-provided subsidy to offset premiums," Moody's said.
"The economics for healthy young individuals do not provide much incentive for them to sign up. For those not eligible for a subsidy, a low-cost plan on the insurance exchange will cost more than $100 per month and will carry a high deductible of several thousand dollars. On the other hand, the penalty for not having health insurance during 2014 is minimal (for an individual, it is limited to the greater of $95 or 1% of income)."
Clare Krusing, spokeswoman for America's Health Insurance Plans, says payers aren't making any rash assessments about the risk pool in the middle of enrollment. "We are still in January and we still have to go through the entire open enrollment process to really understand and at the end of the six-month period what those numbers are going to mean for the marketplace," she says. "But there is broad agreement that you have to have broad participation from young and healthy people for all of these reforms to work."