By Maeve Reston, CNN

(CNN) -- As millions of Americans tuned in for the first night of the Democratic convention, the party strove to broaden their appeal to frustrated Republicans and independents -- weaving together speeches that prosecuted the case against President Donald Trump, with stories from real people about the fatal toll of the pandemic and personal stories that were meant to provide a window into Joe Biden's personal side.

Former first lady Michelle Obama, Vermont Sen. Bernie Sanders and New York Gov. Andrew Cuomo were among the headliners for the first night of programming, which was emceed by actress Eva Longoria. But also on the slate were four Republican politicians and a video montage of GOP voters speaking about why they planned to cast their ballots for Biden.

Obama sought to strike that balance between a message of hope and a condemnation of Trump. She urged Americans not to give in to their baser instincts and "go low" as Trump governs with gutter politics -- and tried to appeal to voters who are frustrated and anxious about the chaos that the President has created, arguing that the America is underperforming "not simply on matters of policy but on matters of character."

"I know that regardless of our race, age, religion, or politics, when we close out the noise and the fear and truly open our hearts, we know that what's going on in this country is just not right. This is not who we want to be," Obama said. "Donald Trump is the wrong president for our country. He has had more than enough time to prove that he can do the job, but he is clearly in over his head. He cannot meet this moment. He simply cannot be who we need him to be for us. It is what it is."

"If you take one thing from my words tonight, it is this," she continued. "If you think things cannot possibly get worse, trust me, they can; and they will if we don't make a change in this election. If we have any hope of ending this chaos, we have got to vote for Joe Biden like our lives depend on it."

It was a stinging rebuke of the President after a night in which most critiques of Trump were cast in contrast to Biden. Convention organizers sought to portray the former vice president as an empathetic figure who genuinely cares for other people, as opposed to his opponent who was compared to a Roman emperor fiddling as his country burns.

How to watch the Democratic National Convention

The convention opened with a virtual choir singing the National Anthem and interviews with Americans grappling with the pandemic and the economic strife, voters who were interviewed by Longoria. The subdued proceedings felt unusual without the typical raucous crowd that such events are usually greeted by as the Democratic Party took on the undertaking of the first convention in the time of coronavirus.

There were awkward moments, but also powerful ones, such as when Philonise Floyd -- the brother of George Floyd, a Black man who was killed when a White police officer held him down with a knee on his neck -- called for a moment of silence to remember Black people killed by law enforcement.

There were spirited defenses of the US Postal Service and an emphasis on voting, with Obama urging Democrats to be prepared to put on a face mask and spend all night standing in line in order to vote for Biden.

Party officials have said that Monday's theme was "We the People" -- with remarks focused on how the country can unite and move forward.

Biden's lead over Trump among registered voters has shrunk significantly since June, according to a new CNN poll conducted by SSRS. But his selection of Harris, the junior senator from California and former attorney general of California, as his running mate has drawn largely positive reviews, according to the poll.

Michelle Obama makes the case for her friend

The former first lady is one of the most admired figures in the Democratic Party and has often served as a voice of optimism during her time in the public eye. But, her remarks on Monday were among the most stark in her career and amounted to a startling rebuke of a sitting president by a former first lady.

Obama's sharply worded critique of Trump called him "the wrong President for our country," calling him a leader who is unfit for office and "in over his head."

"Like so many of you, Barack and I have tried our best to instill in our girls a strong moral foundation to carry forward the values that our parents and grandparents poured into us. But right now, kids in this country are seeing what happens when we stop requiring empathy of one another. They're looking around wondering if we've been lying to them this whole time about who we are and what we truly value," Obama said.

"They see people shouting in grocery stores, unwilling to wear a mask to keep us all safe. They see people calling the police on folks minding their own business just because of the color of their skin. They see an entitlement that says only certain people belong here, that greed is good, and winning is everything because as long as you come out on top, it doesn't matter what happens to everyone else. And they see what happens when that lack of empathy is ginned up into outright disdain."

In her taped address, she also served as a character witness for Biden, who she called "a profoundly decent man guided by his faith" and someone who served as a "terrific vice president" to her husband.

"He knows what it takes to rescue an economy, beat back a pandemic and lead our country. And he listens," Obama said. "He will tell the truth and trust science. He will make smart plans and mange a good team and he will govern as someone who has lived a life the rest of us can recognize."

The former first lady highlighted Biden's empathy explained through the many losses he has weathered in his life, from the car accident that claimed the life of his first wife and his daughter to the death of his son, former Delaware Attorney General Beau Biden, who died from brain cancer in 2015 at the age of 46.

"Joe knows the anguish of sitting at a table with an empty chair. Which is why he gives his time so freely to grieving parents," Obama said in the video, adding that Biden also hands out his personal phone number to children trying to overcome a stutter as he did as a young man. "His life is a testament to getting back up. And he is going to channel that same grit and passion to pick us all up -- to help us heal and guide us forward."

Republicans against Trump speak at the DNC

In an effort to broaden the party's appeal at a time when a new CNN poll shows the race between Biden and President Donald Trump tightening, Democrats turned the microphone over to three Republican women in Monday night's lineup, as well as former Ohio Republican Gov. John Kasich: Meg Whitman, the 2010 Republican nominee for governor of California, who backed Hillary Clinton in 2016; Susan Molinari, a former Republican congresswoman from New York; and Christine Todd Whitman, who headed the Environmental Protection Agency under President George W. Bush and the former governor of New Jersey.

They spoke to the Biden-Harris campaign's hope that Republicans frustrated with Trump will be comfortable enough to set aside their party allegiances in November and pull the lever for Biden. The number of "Republicans for Biden" groups have been steadily growing, with high-profile organizations like the Lincoln Project and others gaining significant attention in their fight against Trump.

The Biden campaign decided against including the Lincoln Project in its convention, a senior Democratic official said.

The speech from Kasich, who ran for president as a Republican in 2016, was intended to combat the argument from the Trump campaign that Biden and Harris are tools of the radical left who will push for dramatic structural change. The message from all of the Republicans who spoke was also targeted at independents, who have increasingly drifted toward Biden's campaign, according to recent polls.

"I'm a lifelong Republican, but that attachment holds second place to my responsibility to my country," Kasich said. "I'm sure there are Republicans and independents who couldn't imagine crossing over to support a Democrat. They fear Joe may turn sharp left and leave them behind. I don't believe that because I know the measure of the man. It's reasonable, faithful, respectful, and, you know, no one pushes Joe around."

The inclusion of Republican speakers drew blowback from progressive groups, but a senior Biden adviser said their speeches were intentionally placed on Monday — on the same evening as Sanders — to show that Biden's candidacy welcomes a broad array of voices.

Sanders aims to avoid intraparty fight

Tying together the unity theme of the night, Sanders hoped to galvanize the many young, progressive voters who supported his campaign four months after he abandoned his own White House bid and backed Biden.

He urged Democrats in his speech to come together and "remove the most dangerous President in history," because "the price of failure is just too great to imagine."

"Together we have moved this country in a bold new direction showing that all of us—Black and White, Latino, Native American, Asian American, gay and straight, native born and immigrant— yearn for a nation based on the principles of justice, love, and compassion," Sanders said.

"Our campaign ended several months ago, but our movement continues and is getting stronger every day. Many of the ideas we fought for, that just a few years ago were considered 'radical,' are now mainstream. But, let us be clear, if Donald Trump is reelected, all the progress we have made will be in jeopardy."

It was a stark contrast to the 2016 convention, when Sanders and his delegates kept the pressure on Hillary Clinton and her campaign until the very end, with numerous signs of divisions playing out during votes on the party's platform and on the convention floor.

Biden and Sanders have not seen each other in person since that one-on-one debate in March but the two speak regularly, the aide said, as their teams have worked closely since April on policy and efforts to unite the party.

Sanders spent much of his speech criticizing Trump, including eviscerating the President's handling of the coronavirus pandemic.

"Nero fiddled while Rome burned; Trump golfs. His actions fanned this pandemic resulting in over 170,000 deaths and a nation still unprepared to protect its people," Sanders said.

Trump's record on race in the spotlight

Washington, DC, Mayor Muriel Bowser described the moment in her city when the Trump administration ordered riot police to move in on peaceful protesters in early June to clear Lafayette Square for a presidential photo op.

"He stood in front of one of our most treasured houses of worship and held a Bible for a photo op," Bowser said, referring to Trump's appearance in front of St. John's Church across from the White House. "He sent troops in camouflage into our streets. He sent tear gas into the air -- and federal helicopters, too. I knew if he did this to DC, he would do it to your city or your town. And that's when I said, 'Enough.' I said 'enough' for every Black and Brown American who has experienced injustice; 'enough' for every American who believes in justice."

Bowser said she commissioned Black Lives Matter Plaza in Washington "as a place where we could come together to say: 'Enough.' "

"By coming together this November to elect Joe Biden and Kamala Harris, we will say: 'Next,'" she said.

Bowser introduced Philonise Floyd, who called for justice for other Black men and women who have been killed by police and then remembered his brother with a moment of silence.

"George had a giving spirit, a spirit that has shown up on the streets around our nation, and around the world—people of all races, all ages, all genders, all backgrounds—peacefully protesting in the name of love and unity," Floyd said, mentioning the names of others who have died in police custody, including Breonna Taylor, Ahmaud Arbery and Eric Garner.

"It's up to us to carry on the fight for justice," he said. "Our actions will be their legacies."

During the moving moment of silence that followed, the Democrats' convention feed showed voters around the nation reflecting on their deaths with their heads bowed.

This story has been updated with additional developments on Monday.