Cindy McCain praises Joe Biden in a new campaign ad, calling him a president who would 'put service before self'

• Cindy McCain, the wife of late Senator John McCain, appeared in an ad in support of the Biden-Harris 2020 campaign.
• In the ad, McCain said Democratic nominee Joe Biden would be "a president who will honor our fallen heroes. And a president who will bring out the best in us. Not the worst."
• President Donald Trump once referred to John McCain, a war veteran, as a "loser," but has vehemently denied doing so.

A new ad released by the Biden 2020 campaign features Cindy McCain, widow of Republican Sen. John McCain, reflecting on her late husband's relationship with the former vice president.

"My husband knew Joe Biden a long time," McCain says in the minute-long ad. "They traveled thousands of miles together, visiting troops overseas. And they developed the kind of friendship you don't see too often."

"In the Senate, they disagreed on almost everything," McCain continued. "They'd fight like hell on the floor, and then they'd go each lunch together. Because they always put their friendship and their country first."

Former Vice President Joe Biden and President Donald Trump continue to battle for voters just weeks before Americans cast a ballot in the upcoming presidential election. Biden maintains a lead over Trump by about 9 percentage points, according to the national polling average from Real Clear Politics.

McCain in the ad appeared to take several jabs at Trump, saying that Biden would be a president "who will put service before self. A president who will lead with courage and compassion, not ego. A president who will respect the sacrifices made by our service members and their families. A president who will honor our fallen heroes. And a president who will bring out the best in us. Not the worst."

Last month, a report from The Atlantic said Trump at one point referred to fallen soldiers as "losers" and "suckers," which he has vehemently denied saying.

Biden quickly blasted Trump for the reported remarks. "If the revelations in today's Atlantic article are true, then they are yet another marker of how deeply President Trump and I disagree about the role of the president of the United States," Biden said.

Trump has referred to John McCain, who died of brain cancer in 2018, as a "loser," mocking his military service five years ago.

"I like people who weren't captured," Trump said at an Iowa summit during his presidential campaign in 2015, referring to John McCain. "I don't like losers."

Cindy McCain endorsed Biden earlier this year and has since been rallying voters on his behalf.

"Joe Biden's dedicated his life to this country and working across the aisle to get things done. Joe will always fight for the American people, just like John did," McCain said in the ad.

The Trump 2020 campaign did not immediately respond to a request for comment from Business Insider.