Here’s the latest on the presidential race.

Former President Donald J. Trump and his running mate, Senator JD Vance of Ohio, rallied in Atlanta on Saturday night, campaigning in a battleground state where Vice President Kamala Harris rallied earlier this week.

Mr. Trump and Mr. Vance held their event in the same 8,000-seat arena where Ms. Harris held her campaign’s largest rally to date. In a meandering speech that lasted more than 90 minutes, Mr. Trump insulted Ms. Harris’s intellect and communication skills and repeatedly attacked her over immigration, crime and inflation. He also tried to relitigate his defeat in Georgia in 2020. “I won the state twice,” he claimed falsely. (President Biden won Georgia by roughly 12,000 votes in 2020, and Mr. Trump has been indicted on charges related to his efforts to reverse his loss there.)

Ms. Harris has no public events on her schedule this weekend, as she is expected to meet with several of the men thought to be finalists to be her running mate. One contender, Gov. Tim Walz of Minnesota, canceled a planned trip to New Hampshire on Sunday. “The governor’s schedule has changed,” his spokesman said.

Ms. Harris is expected to announce her choice by Tuesday, when the new ticket will begin a five-day tour of battleground states.

Here’s what to know:

• Will there be another debate? Mr. Trump has dropped out of an ABC News debate scheduled for Sept. 10 and presented a counterproposal to Ms. Harris, his presumptive opponent, to face off on Fox News six days earlier. The change, which Mr. Trump announced on his social media site, raised objections from the Harris campaign and appeared to throw a potential showdown between the rivals into question.

• Harris has the votes: The Democratic Party announced on Friday that Ms. Harris had secured the support of enough delegates to clinch the party’s nomination, setting her up to become the first Black woman and person of South Asian heritage to earn the top spot on a major political ticket for president. Her nomination will become official when the party wraps up its virtual roll-call vote on Monday.

• Staff moves: On Friday, the Harris campaign announced the addition of several top advisers, including David Plouffe, who managed Barack Obama’s first presidential run. The campaign is also bringing on board Jennifer Palmieri, a former Obama and Clinton communications director; Stephanie Cutter, Mr. Obama’s deputy campaign manager in 2012; and Mitch Stewart, who was Mr. Obama’s battleground states director that same year. Ms. Harris’s brother-in-law and Uber’s chief lawyer, Tony West, is taking a leave from the company to advise her campaign.

• The second gentleman: Hours after a British tabloid reported that Ms. Harris’s husband, Doug Emhoff, had a previously undisclosed relationship approximately 15 years ago with a teacher who worked at his children’s elementary school in California, Mr. Emhoff acknowledged on Saturday that he had an extramarital affair during his first marriage, years before he met Ms. Harris. At the time, Mr. Emhoff was married to Kerstin Emhoff, a film producer. The couple filed for divorce in 2009, and Mr. Emhoff met Ms. Harris in 2013.

Reid J. Epstein contributed reporting.