People, stop wringing your hands and roll up your sleeves. On Sunday, we’ll be just 100 days from the first day of open enrollment in new, high quality and affordable health insurance coverage options. As we barrel towards the finish line, pundits and policymakers have been quick to question whether we can actually pull it off. There’s not enough time, they say. The IT systems won’t work, they say. There won’t be enough health plans for people to choose from, they say. The costs will be too high and people won’t enroll, they say.

How to answer these nabobs of negativism? One way is to point to our recent experience with the launch of another major national health care program. In fact, just 100 days before open enrollment in Medicare’s prescription drug benefit (Part D) in 2005, observers had doomed it to failure, making many of these exact same claims. Yet the Part D program now enrolls 35 million people and has broad, bipartisan public support. And millions of people are able to afford and access prescription drugs that they previously could not.

That’s the core message of a report we’re releasing today, in partnership with our Georgetown University Health Policy Institute colleagues Jack Hoadley and Laura Summer. In our report, supported by the Robert Wood Johnson Foundation, we assess the lead up and launch of the Medicare Part D program, and find that the many challenges faced by that program hold important lessons for those implementing the Affordable Care Act today.

Here are just a few examples of the interesting parallels:

• Low public opinion. Just a few months prior to the launch of Part D, public opinion was actually less favorable to the program than it has been towards Obamacare (In April 2005, 21% had a favorable opinion of Part D, compared to 35% with a favorable opinion of the ACA in April 2013).
• Worries about plan choices. Many feared that insurers would decline to participate in Part D, leaving seniors without sufficient drug plan options. As it turned out, plan participation was robust and every beneficiary had a choice of at least 27 plan options, and most had 40 or more to choose from.
• Questions about readiness. There were extremely tight time frames for the completion of plan reviews and the IT build for the operation of Part D. Pundits questioned whether the Centers for Medicare & Medicaid Services (CMS) could pull it off, but they did. CMS was ready for open enrollment in November of 2005.
• Costs for consumers. Before the start of Part D, many worried that the prescription drug plans would cost too much. Ultimately, Medicare Part D costs were lower than projected.
• Outreach and education challenges. The Bush Administration waged a nationwide, high profile publicity campaign to get the word out about the start of the Part D program. Yet, just before the start of the program, 37 percent of beneficiaries reported they would not enroll in the program, and another 43 percent said they were uncertain. But in spite of the initial lack of interest, by the end of the open enrollment period, 53 percent of beneficiaries were enrolled, and another 16 percent participated through subsidized coverage from former employers.

To be clear, the launch of Medicare Part D was far from perfect. Federal and state officials (who had an important role helping dual eligible beneficiaries transition to the new drug benefit) had to quickly respond to emerging problems, divert resources, make policy changes, and implement technical fixes. And not everything was fixed as fast or to the extent everyone might have liked. In particular, call centers and people providing in-person assistance were under-resourced and often could not obtain the information necessary to effectively advise consumers. CMS had to significantly increase support and training for consumer assistance. And Part D is not a perfect analogue for all of the ACA’s changes—for example, it enrolled seniors who were already eligible for Medicare. The ACA’s eligibility and verification process will be more complicated.

Eight years later, even though flaws remain in the program, it has emerged to become a core part of Medicare, with broad – and bipartisan – support.  And most importantly, it’s fulfilling its mission of making prescription drugs more affordable for America’s seniors.  In fact, perhaps the most surprising thing about the Medicare prescription drug benefit is that it’s only been around for eight years; it’s hard to imagine going back to the pre-Part D days. Chances are, we’ll be able to look back eight years from now and say the same thing about the Affordable Care Act.