Shortly after the news broke last year that McCain had brain cancer, CNN Jake Tapper asked the senator how he wanted the American people to remember him. McCain's reply was concise:

He served his country and not always right. Made a lot of mistakes. Made a lot of errors, but served his country. And I hope we could add honorably.

In 2008, McCain received the GOP's nomination for president, and during his speech at the Republican National Convention, he recalled that his love for the U.S. grew while he was in Vietnam:

I fell in love with my country when I was a prisoner in someone else’s. I loved it not just for the many comforts of life here. I loved it for its decency; for its faith in the wisdom, justice and goodness of its people. I loved it because it was not just a place, but an idea, a cause worth fighting for. I was never the same again. I wasn’t my own man anymore. I was my country’s.

In his new memoir — The Restless Wave, published earlier this year — McCain discussed the increasingly divided nature of American politics, and expressed a wish for more unity:

Before I leave, I'd like to see our politics begin to return to the purposes and practices that distinguish our history from the history of other nations. I would like to see us recover our sense that we are more alike than different.

Long before the Paris Climate Agreement existed, and long before Trump became president withdrew the U.S. from it, McCain was a rare Republican voice in discussing the dangers of climate change. When he was running for president in 2008, McCain distanced himself from Republican opponent George W. Bush during a speech at a wind power plant in Oregon. McCain called for a mandatory limit on greenhouse gas emissions, and discouraged idle behavior on the issue:

Instead of idly debating the precise extent of global warming or the precise timeline of global warming, we need to deal with the central facts of rising temperatures, rising waters and all the endless troubles that global warming will bring. We stand warned by serious and credible scientists across the world that time is short and the dangers are great.

When McCain was running for president in 2000, he called for campaign finance reform and tax cuts for the rich, prompting Bush to and other conservative critics to suggest that he wasn't really a Republican. During a debate in Grand Rapids, Michigan, McCain took on this issue directly:

I am deeply concerned about a kind of class warfare that is going on right now — it's unfortunate — there's a growing gap between the haves and have-nots in America, and that gap is growing and it is unfortunately divided up along ethnic lines.

He later told The New Republic that "big money" was negatively impacting the GOP:

I think the party to some degree has lost its way, and I think this is because of the influence of big money.

When McCain received the Republican nomination in 2008, he addressed Obama and his supporters directly. Whereas Trump still wonders why Hillary Clinton — his opponent in the 2016 presidential election — has not been "locked up," McCain remarked that although "we’re going to win this election," he still wanted to honor Obama's achievement:

Finally, a word to Senator Obama and his supporters. We’ll go at it over the next two months. That’s the nature of these contests, and there are big differences between us. But you have my respect and admiration. Despite our differences, much more unites us than divides us. We are fellow Americans, an association that means more to me than any other. We’re dedicated to the proposition that all people are created equal and endowed by our Creator with inalienable rights. No country ever had a greater cause than that. And I wouldn’t be an American worthy of the name if I didn’t honor Senator Obama and his supporters for their achievement.

Years before Hillary Clinton first ran for president, McCain prompted swift criticism from conservatives after suggesting that Clinton was suitable for the job. During a joint segment with Clinton on MSNBC's Meet the Press back in February 2005, McCain even acknowledged that he was likely to get in trouble for saying the following:

I am sure that Senator Clinton would make a good president. I happen to be a Republican and would support, obviously, a Republican nominee, but I have no doubt that Senator Clinton would make a good president.

During his 2008 and 2010 campaigns, USA Today reported that McCain distanced himself from the "maverick" label he had earned, but he never completely denied it. In August 2017 — less than a month after he cast a deciding vote against repealing Obamacare — McCain told The Arizona Republic that he was, finally, comfortable with being remembered as a maverick, adding:

I also hope that they recognize what I've done on a lot of issues, especially national defense.

Earlier this year, HBO produced a documentary about McCain — his life, his legacy, and his reflection on the current state of American politics. In the past two years, McCain has offered a number of critiques of Trump, but there's a scene in the documentary where his criticism is concise and indirect; it doesn't even mention Trump's name:

We need to give the American people what they deserve. And right now, they're not getting it.

For months, there has been speculation about who would replace him, but McCain insisted that he would remain a senator until his death — and that is precisely what he did.