Critics of Medicare Advantage have long argued that the government is more than generous in paying private plans

Groups like the Better Medicare Alliance say they support providing dental, hearing and vision coverage for all Medicare beneficiaries.

But they worry that congressional leaders won't factor in the cost of the new traditional Medicare benefits into the standard.

This will reduce rebates from the program, which may threaten other supplemental benefits that Medicare Advantage members enjoy.

"Do you think we won't notice?" Says old woman talking in camera. “Do you think you can sneak through this?” An older man adds later. Others warn that Washington is "tampering" with its Medicare Advantage health coverage and trying to raise its premiums.

But the TV ad, pushed by the Better Medicare Alliance, a research and advocacy group for Medicare Advantage plans, doesn't make clear the cuts congressional lawmakers might try to bypass.

Concerned that viewers might feel confused and anxious about coverage changes, we asked the Better Medicare Alliance for details about the subtle moves the organization aims to alert people to. It's not just one ad. The organization has launched a $3 million TV, radio and online ad campaign, according to ad tracker AdImpact.

In response, the group provided this comment via email from its president and CEO, Mary Beth Donahue.

"The Better Medicare Alliance is broadcasting messages encouraging Congress to watch out for reductions in Medicare Advantage coverage for seniors, whether through the standard policies in the Reconciliation Bill or other methods."

While the details are still light on, Donahue's comment provided important details not mentioned in the ad. The group is concerned about reductions in coverage through 'standard policies' in the settlement bill.

Now we can get somewhere. In the Democrats' Climate and Social Expenditure bill being introduced in Congress, one of the major health care proposals would add dental, hearing and vision coverage to the traditional health care program.

The cost of this ruling, endorsed by Senator Bernie Sanders (I-Vt.), is estimated at $350 billion over 10 years. As Democrats struggle to wind down their $3.5 trillion social spending bill to make it palatable to moderates in the party, it's unclear whether the expansion of Medicare benefits will make it to the final version.

Assuming that, here's where the standard calculations come into play, presumably the concerns of the Better Medicare Alliance.