Presidents past and present joined members of Congress from both parties and world leaders in mourning Sen. John McCain and praising him for a lifetime of service and accomplishments.
Former Presidents George W. Bush and Barack Obama, who blocked the Arizona Republican's own White House ambitions, are among those expected to speak at McCain's funeral.
"These were bitter contests, both of them," said Sen. Jeff Flake, R-Ariz., and "to ask them to speak at your funeral, and for them to be honored at the opportunity, that tells you all you need to know."
Flake told CBS' "Face the Nation" that McCain "was quick to forgive - certainly put the good of the country above himself, and the fact that his former opponents will be there speaking says all we need to know."
McCain, 81, died Saturday at his ranch in Arizona after a yearlong battle with brain cancer. He is expected to be remembered at ceremonies in Arizona and Washington this coming week or next, if the family prefers to give more time for Congress to return to the Capitol from its summer recess. McCain is to be buried at the U.S. Naval Academy Cemetery on a peninsula overlooking the Severn River in Annapolis, Maryland. On Saturday, his grave was marked where he had written he wanted to be buried — next to his best friend from his Naval Academy days, Adm. Chuck Larson.
Cindy McCain was by her husband's side with other members of the family when he died Saturday at 4:28 p.m., according to a statement from McCain's office. On Friday, the family had announced that McCain was ending medical treatment for brain cancer.
"My heart is broken," Cindy McCain said on Twitter. "I am so lucky to have lived the adventure of loving this incredible man for 38 years. He passed the way he lived, on his own terms, surrounded by the people he loved, in the the place he loved best."
McCain's daughter Meghan posted a lengthy note about her "beloved father" on Twitter, writing, "I was with my father at his end, as he was with me at my beginning."
"All that I am is thanks to him. Now that he is gone, the task of my lifetime is to live up to his example, his expectations, and his love," she wrote.
She said that in her sorrow she took comfort that "John McCain, hero of the republic and to his little girl, wakes today to something more glorious than anything on this earth."
President Donald Trump, who once criticized McCain for being taken prisoner during the Vietnam War, said his "deepest sympathies and respect" went out to McCain's family. First lady Melania Trump tweeted thanks to McCain for his service to the country. Trump's brief Twitter statement said "hearts and prayers" are with the McCain family.
Trump and McCain were at odds until the end. The president, who as a candidate in 2016 mocked McCain's capture in Vietnam, had jabbed at the ailing senator for voting against Republican efforts to roll back President Barack Obama's health care law.
Earlier this summer, McCain issued a blistering statement criticizing Trump's meeting with Russian President Vladimir Putin.
Obama, who triumphed over McCain in 2008, said that despite their differences, McCain and he shared a "fidelity to something higher - the ideals for which generations of Americans and immigrants alike have fought, marched, and sacrificed."
Obama said they "saw our political battles, even, as a privilege, something noble, an opportunity to serve as stewards of those high ideals at home, and to advance them around the world."
Bush, who defeated McCain for the 2000 Republican presidential nomination, called McCain a "man of deep conviction and a patriot of the highest order" and a "friend whom I'll deeply miss."
Other tributes poured in from around the globe.
French President Emmanuel Macron tweeted in English that McCain "was a true American hero. He devoted his entire life to his country." Israel's prime minister, Benjamin Netanyahu, said McCain's support for the Jewish state "never wavered. It sprang from his belief in democracy and freedom." And Germany's chancellor, Angela Merkel, called McCain "a tireless fighter for a strong trans-Atlantic alliance. His significance went well beyond his own country."
McCain was the son and grandson of admirals and followed them to the U.S. Naval Academy. A pilot, he was shot down over Vietnam and held as a prisoner of war for more than five years. He went on to win a seat in the House and in 1986, the Senate, where he served for the rest of his life.
Colleagues from both sides of the aisle issued heartfelt statements remembering their fellow lawmaker. Senate Majority Leader Mitch McConnell, R-Ky., called McCain a "fascinating personality."
"He would occasionally be in a bad place with various members, including myself, and when this would blow over it was like nothing ever happened," McConnell said Saturday after a GOP state dinner in Lexington, Kentucky. "He also had a wicked sense of humor and it made every tense moment come out better."
House Speaker Paul Ryan called McCain's death "a sad day for the United States."
"Our country has lost a decorated war hero and statesman," he tweeted. "John McCain was a giant of our time—not just for the things he achieved, but for who he was and what he fought for all his life."
Sen. Lindsey Graham, R-S.C., said of his colleague that "America and Freedom have lost one of her greatest champions."
He added that he'd "lost one of my dearest friends and mentor."
Former Alaska Gov. Sarah Palin, whom McCain tapped as his running mate for vice president in 2008, tweeted that he "was a maverick and a fighter, never afraid to stand for his beliefs. John never took the easy path in life - and through sacrifice and suffering he inspired others to serve something greater than self."
Palin added in another tweet that McCain was her friend and she "will remember the good times."
Former President Clinton and his wife, former secretary of state and 2016 Democratic presidential nominee Hillary Clinton, said that McCain was a "skilled, tough politician, as well as a trusted colleague alongside whom Hillary was honored to serve in the Senate."
"He frequently put partisanship aside to do what he thought was best for the country, and was never afraid to break the mold if it was the right thing to do," the statement said.
Former Vice President Joe Biden, who developed a friendship with McCain while they served together in the Senate, said the Arizona lawmaker will "cast a long shadow."
"The spirit that drove him was never extinguished: we are here to commit ourselves to something bigger than ourselves," Biden said
The Senate's top Democrat, New York's Chuck Schumer, said he wants to rename the Senate building that housed McCain's suite of offices after McCain.
"As you go through life, you meet few truly great people. John McCain was one of them," Schumer said. "Maybe most of all, he was a truth teller - never afraid to speak truth to power in an era where that has become all too rare."
Gov. Doug Ducey, R-Ariz., does not plan to announce his selection of a Senate successor to McCain until after McCain's burial. Under state law, the governor's appointee to serve until the next general election in 2020 must come from the same political party. A statement from Ducey's office said that "now is a time for remembering and honoring a consequential life."
NBC's Daniel Macht contributed to this report.