CHICAGO (AP) — Former President Barack Obama, Michelle Obama and second gentleman Doug Emhoff will speak Tuesday on the second day of the Democratic National Convention, turning the party's attention toward Vice President Kamala Harris and her faceoff against Republican Donald Trump.

The Harris campaign said Tuesday it will spotlight "trusted messengers" from key battleground states over the convention's three remaining days. They include Sen. Catherine Cortez Masto of Nevada; Gov. Gretchen Whitmer, Sen. Gary Peters and Rep. Elissa Slotkin of Michigan; Sen. Bob Casey of Pennsylvania and Sen. Tammy Baldwin of Wisconsin. From Arizona, Sen. Mark Kelly will speak along with John Giles, the Republican mayor of Mesa.

Gov. Roy Cooper of North Carolina — a state that voted for Trump in 2020 but is now a major pickup opportunity for Harris — will be among the final speakers before Harris accepts the Democratic presidential nomination on Thursday.

Offering the prime spots to local elected leaders — many of whom poll better than the top of the ticket in their home states — is a deliberate move to reach undecided voters and maximize Harris' pathways to 270 electoral votes, her campaign said.

Harris also announced Tuesday an array of prominent Republicans set to speak at the convention, including former U.S. Rep. Adam Kinzinger of Illinois, former Georgia Lieutenant Gov. Geoff Duncan and former Trump White House staffers Olivia Troye and Stephanie Grisham. All are now critics of Trump.

The pivot toward the presidential campaign's final 76 days follows an opening night that was designed to give a graceful exit to the incumbent president, who was greeted with a hero's welcome for stepping aside for Harris.

Speaking clearly and energetically, President Joe Biden appeared to relish the chance to defend his record, advocate for his vice president and assail Trump. His delivery was more reminiscent of the Biden who won in 2020 than the mumbling and sometimes incoherent one-time candidate whose debate performance against Trump in June sparked the downfall of his reelection campaign.

Biden, in his remarks, repeated his 2020 theme that "we're in a battle for the very soul of America," and pressed the case for why Harris and her running mate Tim Walz were best prepared to wage it.

"Because of you, we've had the most extraordinary four years of progress ever, period," Biden declared. And then he interjected, "I say 'we,' I mean 'me and Kamala,'" sharing the credit for his most popular successes with the vice president to whom he handed over his political operation.

Harris made a brief, unannounced appearance at the convention on Monday to thank Biden for his leadership. She later joined him on stage, where the two spoke and hugged.

"Joe, thank you for your historic leadership, for your lifetime of service to our nation, and for all you'll continue to do," she said. "We are forever grateful to you."

The opening day ran more than an hour behind schedule and forced some planned speakers, including musician James Taylor, to be dropped from the program, which convention organizers attributed to sustained applause for speakers.

Harris will travel Tuesday to Milwaukee for a rally in the swing state of Wisconsin before returning to Chicago late in the evening.