Sen. John McCain — an American war hero and veteran Arizona senator — died Saturday after a long battle with brain cancer. He was 81.

McCain’s legacy spans a lifetime of public service as a former naval pilot, prisoner of war, U.S. senator and Republican presidential nominee.

He was also a level-headed voice in the world of politics, where he brought civility and courteousness to a political system that often lacked basic decency. McCain always took the high road.

In 2008, as then-candidate for president, McCain took a question from a voter who brought up a racist conspiracy theory against then-candidate Barack Obama.

McCain cut the voter off, took the microphone and defended Obama before a large crowd of supporters and the TV cameras.

“I can’t trust Obama. I have read about him, and he’s not — he’s an Arab,” the woman told McCain during a town hall meeting in Minnesota.

McCain quickly interrupted her thought and replied, “No ma’am.”

“He’s a decent family man, citizen, that I just happen to have disagreements with on fundamental issues, and that’s what the campaign is all about,” he replied. “He’s not.”

WATCH: McCain Counters Obama ‘Arab’ Question