Story highlights The AARP is one of many outside groups looking to pressure lawmakers

America First Policies also released its first Obamacare ad

Washington (CNN) AARP is pitching a message directly to seniors who supported Donald Trump for president as the debate over the Republican health care bill enters the home stretch.

The advocacy organization is running a radio ad challenging Trump's identity as a change agent and arguing that the bill to be decided in the House of Representatives on Friday serves as an "age tax" on the elderly.

"You walked into the voting booth. You thought it through. You cast your ballot. But the new health care bill in Congress is not the change you voted for. In fact, it's loaded with everything you voted against," the spot says. "That's not the change you had in mind when you cast your ballot. And that's why you should call you member of Congress today."

The AARP is one of many outside groups looking to pressure lawmakers ahead of a tough vote to repeal and replace Obamacare, but is one of the few running ads directly speaking to Trump voters and asking them to vote against his interests. The organization says it is a six-figure buy that began airing in targeted congressional districts this week.

Also on Friday, one pro-Trump political group that was expected to be a major player in the debate, America First Policies, unveiled its first ad intended to boost Trump's argument against Obamacare.

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