Democratic heavy-hitters sought to bring the party together on the inaugural day of the Democratic National Convention, which was often marked by jeers and protests in its early hours.
But by the time the highest profile speakers took the stage, the mood seemed to shift.
First Lady Michelle Obama electrified the crowd at the Wells Fargo Center with a speech in which she offered resounding support of presumptive Democratic nominee Hillary Clinton and said the party's principles are on the line.
There's "only one person I believe is truly qualified to be president of the United States and that's our friend, Hillary Clinton," Obama said.
She later added: "I'm with her."
Obama was the only speaker to fully unify a convention divided between supporters of Clinton and Bernie Sanders.
New Jersey Sen. Cory Booker, a Clinton backer, sought to heal some of the division with a prime-time speech that hit on many issues Sanders advocated during the primary, including economic inequality.
"We have a presidential nominee in Hillary Clinton who knows that, in a time of stunningly wide disparities of wealth in our nation, America's greatness must not be measured by how many millionaires and billionaires we have, but by how few people we have living in poverty," Booker said.
The speeches capped a day in which Democratic divisions ripped into the open following leaked emails showing Democratic National Committee leaders displaying hostility toward Sanders. The emails reinforced arguments from Sanders supporters that the party establishment worked against him during the primary.
The challenge for the party was made clear earlier in the evening when comedienne Sarah Silverman, a supporter of Bernie Sanders, sought to bring the Vermont senator's supporters to Hillary Clinton's side.
"Hillary is our Democratic nominee and I will proudly vote for her," Silverman told the convention crowd. "I will vote for Hillary with gusto."
Her comments -- for a time -- seemed to bring the crowd together. But she later let her frustration show, telling so-called Bernie or Bust members they were being "ridiculous" -- comments that led to a very divided reaction among delegates in the Wells Fargo Center.
Sanders himself spent much of Monday making a last-ditch effort to quell the anger among his backers. That frustration was on display when Sanders himself was booed earlier Monday when he urged backers to support Clinton.
Storms hit media tent
A huge thunderstorm has forced hundreds of journalists out of a media tent next to the Wells Fargo Center -- the host of the Democratic National Convention.
Water is dripping into the media tent, soaking electrical equipment, reporters there said on Twitter.
Journalists were advised shortly after 7 p.m. ET that the media tent, which was set up as a workspace for the hundreds of journalists on hand for the convention, was not suited to withstand a direct lightning strike.
They were directed into Lincoln Financial Field, the home of the Philadelphia Eagles football team and near the Wells Fargo Center, the home of the NBA's 76ers and host venue for the convention.
The storm had winds of up to 50 mph and heavy rain, according to the National Weather Service. A flash flood warning was in place in Philadelphia through midnight.
It capped off a day of complaints from journalists about the DNC's logistics in Philadelphia -- particularly compared to the Republican National Convention in Cleveland last week.
Coming Tuesday
The most important order of business: Democrats will officially make Clinton the first female presidential nominee from a major party with the roll call vote.
Later in the evening, Bill Clinton, the first of two former presidents to address the convention, will make the case for his wife's election.
The theme of the day, though, will be driven by the "Mothers of the Movement" -- a group of speakers that includes the mothers of Eric Garner, Michael Brown, Sandra Bland and more, all men and women who died in police custody or as a result of police actions. Trayvon Martin's mother, whose son died at the hands of neighborhood watch volunteer George Zimmerman, will also speak.