Cindy McCain, wife of John McCain, touches the casket during the ceremony honoring the late Senator inside the rotunda of the U.S. Capitol, August 31, 2018 in Washington, DC.

Abraham Lincoln. John F. Kennedy. Ronald Reagan. Rosa Parks. Unknown soldiers. Sen. John McCain has joined the American pantheon of heroes who were honored by lying in state under the rotunda at the U.S. Capitol.

A solemn ceremony began Friday morning in the rotunda. Later, the public was being allowed to file past his flag-draped coffin to pay respects to the senator, who died Saturday, four days before his 82nd birthday. Anyone in line until 8 p.m. ET Friday will be allowed to do view the casket, according to the senator's office.

McCain, who survived nearly six years as a prisoner of war in North Vietnam and served 31 years in the Senate, died after a yearlong fight against brain cancer. He had succeeded Barry Goldwater to represent Arizona in the Senate, lost a White House bid to freshman Sen. Barack Obama and became an outspoken critic of President Donald Trump, a fellow Republican. Trump said during his presidential campaign that McCain was "not a war hero" because he had been captured by North Vietnam.

Read his full obituary: Sen. John McCain, hero POW, former presidential hopeful and maverick Republican, dies at age 81.

Also see: John McCain: Life and times of an American maverick in photos

U.S. presidents are among those entitled to lay in state at the Capitol. The occasions are authorized by a congressional resolution or approved by the congressional leadership, according to the Architect of the Capitol's office.

Before McCain, the honor had been conducted 32 times, starting with former House Speaker Henry Clay on July 1, 1852, according to a list kept by the office. Lincoln was next, from April 19–21, 1865. The Rev. Billy Graham was the most recent, on Feb. 28–March 1. The occasions included three involving unknown soldiers, from the two World Wars and the Korean and Vietnam wars.

Speakers on Friday included Senate Majority Leader Mitch McConnell, R-Ky., House Speaker Paul Ryan, R-Wis., and Vice President Mike Pence. McCain made clear that Trump was not to be invited.

"It is deeply humbling to stand before you today to commemorate the life and service of an American patriot, Senator John McCain," Pence said. "The president asked me to be here on behalf of a grateful nation to pay a debt of honor and respect to a man who served our country throughout his life, in uniform and in public office. And it's my great honor to be here."

McCain's remains arrived Thursday at Joint Base Andrews, Maryland, after a memorial service in Phoenix.