The Affordable Care Act is a landmark health care law that President Obama signed to help millions of Americans and their families afford and keep quality health care coverage. But Mitt Romney has said that on “day number one of my presidency, I will get a waiver from Obamacare for all 50 states and I will see that it is repealed.”

The Affordable Care Act has provided significant benefits for America’s seniors. Take a look at how the health care law has improved the lives of millions of seniors and how Romney’s repeal could jeopardize their health care:

Before the health care law:

• Millions of seniors fell into the Medicare “doughnut hole”—a gap in prescription drug coverage that forced seniors to pay out of pocket, sometimes thousands of dollars, for medication.

• Preventive services under Medicare often came with a co-pay, deductible, or coinsurance.

With the health care law:

• Seniors who fall into the “doughnut hole” coverage gap can now get 50 percent discounts on brand name prescriptions and 14 percent discounts on generic drugs. This crucial reform allowed seniors and people with disabilities to save an average of $600 in 2011. In 2020, the “doughnut hole” gap will be closed for good.

• Now, preventive services including annual checkups, flu shots, mammograms, cancer screenings, and blood pressure tests are free of charge.

Who would Romney’s repeal actually hurt?

At least 3.6 million Americans have already benefited from the “doughnut hole” discounts. 25.7 million people enrolled in traditional Medicare received at least one free preventive benefit in 2011 and, combined with those enrolled in Medicare advantage plans, about 32.5 million people on Medicare benefited from preventive health services with no cost sharing.

If Romney repealed the law, millions of seniors and people with disabilities will struggle to pay for the medications and the quality health care that they’ve earned and deserve.