PHILADELPHIA — Their political fates now entwined, President Barack Obama is imploring voters to elect Hillary Clinton to the White House, joining a chorus of Democrats vouching Wednesday night for her readiness to be commander in chief at time of volatility around the world.
"Even in the middle of crisis, she listens to people, and keeps her cool, and treats everybody with respect," Obama said in excerpts released ahead of his remarks at the Democratic convention. "And no matter how daunting the odds, no matter how much people try to knock her down, she never, ever quits."
For Democrats, Obama's address moment was steeped in symbolism, the passing of the baton from a barrier-breaking president to a candidate trying to make history herself.
His robust support for Clinton, his political foe-turned-friend, is also driven by deep concern that Republican Donald Trump might win in November and unravel the president's eight years in office.
Trump fueled more controversy Wednesday when he encouraged Russia to meddle in the presidential campaign — even as he dismissed suggestions from Obama and other Democrats that Moscow was already acting on his behalf. On the heels of reports that Russia may have hacked Democratic Party emails, Trump said, "Russia, if you're listening," it would be desirable to see Moscow find and publish the thousands of emails Clinton says she deleted during her years as secretary of state.
To Obama and Clinton, Trump's comments only fed their contention that the billionaire businessman is unqualified to be commander in chief. Trump has no national security experience and few ties to the norms that have governed U.S. foreign policy under presidents from both parties, including standing by NATO allies threatened by countries including Russia.
"Donald Trump, who wants to be president of the United States, is asking one of our adversaries to engage in hacking or intelligence efforts against the United States of America to affect our election," Leon Panetta, Obama's former Pentagon chief, said in his convention address.
Wednesday night's Democratic lineup was aimed at emphasizing Clinton's own national security credentials, a shift from two nights focused more on re-introducing her to voters as a champion for women's issues, children and families. Democrats spent little time discussing terrorism or the Islamic State group this week, though there was significantly more focus on those threats Wednesday.
The convention's third night was also a time for Democrats to celebrate Obama's eight years in office. Vice President Joe Biden, who decided against running for president this year after the death of his son, called it a "bittersweet moment."
He appealed directly to the working class white voters who have been drawn to Trump's populism, warning them against falling for false promises and exploitation of Americans' anxieties.
"There's only one person in this election who will help you, there's only one person in this race who will be there for you," he declared. "That's Hillary Clinton's life story."
Of Trump, he said, "This guy doesn't have a clue about the middle class."
Clinton's running mate, Virginia Sen. Tim Kaine, was also addressing the convention, his highest profile opportunity to introduce himself to the nation.
In a move aimed at broadening Clinton's appeal, New York City Mayor Michael Bloomberg — an independent who considered launching a third party bid for president — will endorse the Democratic nominee.
Clinton's campaign believes Trump's unorthodox candidacy will turn off moderate Republicans, particularly women, who worry he's too unpredictable to take the helm in a turbulent world. They recognize that Republicans, as well as many Democrats, have questions about Clinton's character but hope to ease those concerns.
Still, the core of Clinton's strategy is putting back together Obama's winning White House coalition. In both his campaigns, Obama carried more than 90 percent of black voters, the overwhelming majority of Hispanics, and more than half of young people and women.
That coalition was vividly on display in the first two nights of the convention in Philadelphia. Women lawmakers were prominently featured, along with young activists, immigrants, and mothers whose black children were victims of gun violence or killed during encounters with law enforcement.
Gun violence continued as a theme Wednesday night as families of mass shooting victims took the stage. Delegates rose in an emotional standing ovation for the mother of one of the victims in last month's Orlando nightclub shooting, who asked why "commonsense" gun policies weren't in place when her son died.
"I never want you to ask that question about your child," Christine Leinonen said.
Capping the somber section of the program focused on gun violence, a group of Broadway singers performed a rousing rendition of "What the World Needs Now Is Love," as the audience sang and swayed in unison.
Clinton's convention has been awash in history, with energized delegates celebrating her formal nomination as the first woman to ever lead a major political party in the general election. Some supporters of Clinton's primary rival, Bernie Sanders, continued to voice their displeasure.
But Sanders, meeting with New England delegates, said, "As of yesterday, I guess, officially our campaign ended."