For more than 22 years, I served as mayor and a councilperson of Philadelphia. Now, at the age of 61, I have been looking at my AARP newsletters, and listening to my daughter tell me that I'll soon be able to ride SEPTA as a senior for free! I've also been reflective, thinking about next steps, always with the goal of making things better for the people who live and work here. People my age start taking stock of their lives — and asking themselves, "What do I want to do next?"

Many of my fellow baby boomers likely relate to this sentiment – that there is still so much to do, things to accomplish, people to help, more life to experience.

I've been thinking about this constantly since I left City Hall in 2016 and I recently realized that ensuring the most vulnerable in Philadelphia have access to the same kind of high-quality health care that I have should be my focus. While I was in public service, I was passionate about improving our health-care system. The Affordable Care Act made major advancements, but more needs to be done.

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In particular, far too many senior citizens in Philadelphia are still struggling with paying their medical bills. Yes, all Americans over age 65 have access to Medicare, but traditional Medicare has many gaps. It doesn't cover dental, vision or hearing – and you have to sign up and pay for Medicare Part D if you want it to include prescription drugs. Then there is the 20 percent coinsurance  in traditional Medicare. The costs add up, quickly, especially if you're a senior on a fixed income, or if you're hospitalized.

There is a solution for this dilemma – and it's not complicated: Medicare Advantage. Medicare Advantage is a part of the Medicare system, but it functions much more like employer-based health insurance. Medicare Advantage covers drugs, vision, dental, and hearing, and has an out-of-pocket cap to protect consumers from huge co-pays. In most cases Medicare Advantage plans cost the same or less than traditional Medicare premiums.

The problem is that not enough of our seniors sign up for Medicare Advantage. More than 250,000 people in Philadelphia qualify for Medicare, but only 112,000 – less than half of the eligible population – are on a Medicare Advantage plan. That means nearly 10 percent of Philadelphians aren't getting the most comprehensive health coverage that is readily available to them.

Part of my work in this next phase of my life will be dedicated to spreading the word about the benefits of Medicare Advantage in Philadelphia. To do this, I decided to partner with Clover Health, a health-tech company that operates extensively in New Jersey and is now expanding into Philadelphia.

What makes Clover Health unique, and why I chose to work with them, is how they combine technology with compassion, quality medical care, and a focus on prevention.

They go beyond normal Medicare Advantage, using a high-tech approach to deliver proactive results to their members – keeping them healthy and enjoying their lives. They serve seniors by sending nurse practitioners for in-home visits when they feel a person is at risk of high blood pressure, hasn't taken their medicine, or is having trouble managing their sugar and diabetes.

Seeing the Clover staff in action providing personalized, caring, inclusive and affordable healthcare made it clear to me that they were the right partner for me and for Philadelphia. The timing is also right. Everyone on Medicare is able to switch to a Medicare Advantage plan during the Annual Enrollment Period, which begins Oct.  15.

So, Philadelphia, you may start hearing my voice on the radio or seeing me on TV talking about my new cause. And if you or your parents sign up for our Medicare Advantage plan, then I'll know the message is getting through.

Michael Nutter was the mayor of Philadelphia from 2008 to 2016, and is a senior adviser for Clover Health.