CHICAGO (AP) — The Democratic National Convention's second night showcased a double dose of Obama firepower to validate Vice President Kamala Harris and deliver an unsparing indictment of Republican Donald Trump. The convention also served up a raucous roll call of states that was essentially one big dance party.

Harris and her running mate, Minnesota Gov. Tim Walz, ducked out of Chicago to hold a rally just up the interstate in Milwaukee, wooing voters in battleground Wisconsin. It was a recognition that, regardless of whatever good vibes may exist at the convention, Democrats expect this presidential election to be razor-close.

Here are some takeaways from the convention's second night.

The ex-presidents club

If the Republican convention was all about Trump, the Democrats on Tuesday wanted to put Harris in a pantheon with past presidents.

The biggest validators of the night were former President Barack Obama and his wife, Michelle. The latter linked Harris with her husband by telling the rapt crowd, "America, hope is making a comeback."

Barack Obama, for his part, reached back to his own 2004 convention speech to tie Harris to his legacy. "I am feeling hopeful -- because this convention has always been pretty good to kids with funny names who believe in a country where everything is possible," he said.

It wasn't just the Obamas making the case for the vice president. The grandsons of Jimmy Carter and John F. Kennedy also portrayed her as the natural heir of past Democratic leaders.

As groundbreaking as Harris' candidacy is as the first woman of color to be her party's nominee, these speeches by an ex-president and presidential progeny were all about linking her to a broader historical arc and evoking the excitement of Obama's 2008 run that Harris hopes to replicate.

Diverting from the high road

The Obamas did not hold back in lacing into Trump. Michelle Obama's well-worn adage from years past that "when they go low, we go high" no longer seemed operative.

Barack Obama called Trump "a 78-year-old billionaire who hasn't stopped whining about his problems since he rode down his golden escalator nine years ago."

Michelle Obama also took a personal swipe, saying: "For years, Donald Trump did everything in his power to try to make people fear us. His limited and narrow view of the world made him feel threatened by the existence of two hardworking, highly educated, successful people who also happened to be Black."

Playing off her famous line about Republicans going low, Michelle Obama suggested that Trump was going "small" and that "it's unhealthy, and quite frankly, it's unpresidential."

DNC dance party

Political conventions technically happen so that delegates can nominate presidential and vice presidential candidates.

This year, the Democrats took care of that job in advance. But that didn't stop them from holding a ceremonial do-over and turning it into a raucous dance party.

DJ Cassidy strode on stage in a bright blue double-breasted suit and spun tunes for every state as they nominated Harris and Walz. Minnesota got "1999" by native son Prince, Kansas got "Carry on Wayward Son" by, well, Kansas. "Born in the U.S.A." by Bruce Springsteen played as New Jersey weighed in.

Usually it was governors or state party chairs calling out the votes, but some states passed the mic to make serious points. Kate Cox, who unsuccessfully sued her home state of Texas while seeking an abortion for a non-viable fetus, announced Texas' votes. A survivor of the 2017 Las Vegas strip gun massacre announced Nevada's votes.

The roll call highlight was when Atlanta rapper Lil Jon strode through the United Center to the beats of "Turn Down for What," his song with DJ Snake, and rapped his support for Harris and Walz.

Democrats are eager to highlight how Harris' ascension has energized the party. The roll call fit that vibe.

America's blind date with Doug Emhoff

Doug Emhoff wants America to love his wife as much as he does.

His convention speech Tuesday night focused on their love story and offered a personal glimpse meant to pull in voters, too. He dished on the deets of their first phone call, after he left her a rambling voicemail that she still makes him listen to every year on their anniversary.

"I love that laugh," he said adoringly, a rebuttal to Trump's criticism of Harris' laughter.

As Harris flew back to Chicago from Milwaukee after her rally there, Air Force Two spent an extra 10 minutes in the air so she could watch her husband speak, according to an aide.

Emhoff said he "just fell in love fast" with Harris, adding that she finds "joy in pursuing justice" and "stands up to bullies." It's not how most husbands describe their partners, but, then, Emhoff is trying to convince voters that the woman he's been married to for 10 years this Thursday knows how to take on Trump.

A message for Republicans: It's OK to quit Trump

The Democrats are making a play for disaffected Trump voters — and they used one of his former White House staffers to make their case.

Stephanie Grisham worked in various roles in the Trump White House, including communications director and press secretary, allowing Democrats to argue that those who know Trump best have seen him at his worst.

"He has no empathy, no morals, and no fidelity to the truth," Grisham said. "I couldn't be part of the insanity any longer."

Kyle Sweetser, a Trump voter from Alabama, told the convention the former president's tariffs made life harder for construction workers like him. Republican Mayor John Giles of Mesa, Arizona, also spoke about why he's backing Harris. Giles sees Trump's policies as hurting cities like his.

A weighty prop to drive home the Democrats' message on Project 2025

Each day of the DNC is to feature a speaker brandishing an oversized tome designed to represent the Project 2025 policy book from the conservative Heritage Foundation.

Project 2025 is on one hand a very typical Washington effort, uniting a bunch of wonks and activists to map out a potential agenda for the next president. In this case, the authors include many officials who served in Trump's administration and remain close to the candidate. Its organizers say they've gotten dozens of conservative groups to sign on to the push, making it far more meaningful than the average collection of policy papers.

Democrats use Project 2025 as shorthand for their warnings about what might transpire in a second Trump term, particularly potential revisions to civil service rules to ensure more of the federal workforce is loyal to the president. But it's also got page after page of other proposals, grist for attacks from the convention podium.

On Tuesday, it was Pennsylvania state Rep. Malcolm Kenyatta's turn to wave the big book. "It is a radical plan to drag us backwards," he declared.

Michigan Sen. Gary Peters didn't wield the prop, but name-checked the initiative.

And Harris chimed in from Milwaukee, telling the rally crowd, "Can you believe they put that thing in writing?"