Saying he's more optimistic about the country than ever before, President Barack Obama said Wednesday there's never been a man or a woman — "not me, not Bill" — who's more qualified than Hillary Clinton to be president.

In his speech at the Wells Fargo Center in Philadelphia, he said, "Nothing truly prepares you for the demands of the Oval Office. Until you’ve sat at that desk, you don’t know what it’s like to manage a global crisis or send young people to war. But (Clinton) has been part of those decisions."

Arriving to chants of "Yes, we can," Obama also defended his two terms in the White House, citing a rebounding economy and resilience in the face of global terror threats.

“The America I know is full of courage, and optimism, and ingenuity. ... Sure, we have real anxieties — about paying the bills, protecting our kids, caring for a sick parent. We ... are shocked and saddened by the madness of Orlando or Nice. ...

“But as I’ve traveled this country, through all 50 states; as I’ve rejoiced with you and mourned with you, what I’ve also seen, more than anything, is what is right with America," Obama said.

 

The president headlined the night's speakers and followed vice presidential candidate Tim Kaine, who tore into Republican presidential nominee Donald Trump as a "guy who promises a lot" but follows up with "believe me." Kaine underscored his work on the Senate Armed Services and Senate Foreign Relations and Budget committees.

Other speakers included Vice President Joe Biden and wife, Jill; Michael Bloomberg; former congresswoman Gabrielle Giffords and Mark Kelly; and Christine Leinonen, the mother of a Pulse shooting victim. Leinonen, accompanied by Pulse survivors Brandon Wolf and Jose Arraigada, is the mother of Drew Leinonen, who was killed in the attack in Orlando.

The Rev. Jesse Jackson said if elected to the White House, Clinton will advocate progressive policies, push for a fair Supreme Court and gun control. Jackson said she understands the importance of the Black Lives Matter movement and also said Sanders has energized the 2016 race.

"The Bern must never grow old," Jackson said, but that "it's healing time. It's hope time. It's Hillary time."

Earlier in the day, some Bernie Sanders supporters rejected calls for party unity, even as their former presidential candidate continued to try to rally Democrats behind Clinton. Thousands have taken to the streets during the convention to support the Vermont sentor and his progressive agenda.

Information from the Associated Press was used in this report.