CHICAGO — Uncommitted delegates to the Democratic National Convention pressed their demands for a speaking slot on Thursday to address conditions in Gaza, gaining support from several individuals and groups at the convention, even as organizers sought to preserve the party’s show of unity.

On the final day of the convention, pro-Palestinian activists and delegates continued to hold vigils and news conferences to broadcast their disappointment with Democratic leaders who, following weeks of negotiations, declined to give them a speaking slot during the four-day event. The dispute has exposed tensions amid the otherwise celebratory mood that has followed Vice President Kamala Harris’s ascent to the top of the Democratic ticket.

Rep. Alexandria Ocasio-Cortez (D-N.Y.), a leader of the party’s left-leaning faction who gave a fiery speech in defense of Harris on the first night of the convention, saying the vice president has worked “tirelessly” to end the Gaza war, called on the Democratic National Committee late Wednesday to “change course” and allow a speaker to discuss the suffering in the Palestinian enclave.

“Just as we must honor the humanity of hostages, so too must we center the humanity of the 40,000 Palestinians killed under Israeli bombardment,” Ocasio-Cortez posted on X.

The United Auto Workers union, a major supporter of the Democratic ticket, issued a statement saying that if “we want to win this election, the Democratic Party must allow a Palestinian American speaker to be heard from the DNC stage tonight.” Many UAW workers live and vote in Michigan, a crucial swing state that is home to a large Arab American population.

A relative of a hostage being held by Hamas also spoke out in favor of allowing a pro-Palestinian speaker.

The Harris campaign defended its decision and pointed to Harris’s posture on the war in Gaza, saying it presents a “stark contrast” with Republican presidential nominee Donald Trump. Many pro-Palestinian activists also say the Harris campaign has been far more willing to engage with them than President Joe Biden’s team was.

Democrats have “a vice president who is committed to ending the violence, ending the conflict, making sure that we resolve this conflict with a permanent cease-fire that allows Israel to fully secure itself” and “also makes sure that Gazans are able to peacefully live and prosper in Gaza,” Harris communications director Michael Tyler told reporters.

Pro-Palestinian activists at the convention said it is inappropriate to deny them a five-minute speaking slot, given the magnitude of the carnage in Gaza.

The conflict in Gaza originated when Hamas militants broke through a border fence with Israel on Oct. 7, killing some 1,200 people and taking another 250 hostage. In response, Israel has mounted a major military offensive in the Palestinian enclave with the stated aim of destroying Hamas, resulting in more than 40,000 deaths, according to the Gaza Health Ministry.

Pro-Palestinian delegates ramped up their call for a speaking slot after a decision was made Wednesday to allow the parents of an American-Israeli hostage to speak on the main stage. Some of the pro-Palestinian activists said they supported that decision, and they praised Rachel Goldberg and Jon Polin for not only delivering an emotional speech about their son’s 320 days in captivity but also speaking empathetically about Palestinian suffering.

Polin and Goldberg recounted how their son, Hersh Goldberg-Polin, had his left forearm blown off before he was taken hostage into Gaza. They were greeted by a sustained standing ovation and chants of “Bring them home.”

The activists said it was unfair that a Palestinian American would not be given the same opportunity to speak firsthand about the suffering in Gaza. “We started pressing more when we found out the convention was going to give a prime-time spot to families of hostages, which we fully support,” said Waleed Shahid, a founder of the “uncommitted” movement.

Alana Zeitchik, an Israeli American who has a family member held captive by Hamas, posted on X, “Rachel and Jon deserved every second on that stage. I also believe a Palestinian American voice deserves to be heard on that stage.”

After weeks of negotiations, the Harris campaign this week met some of the demands of the Uncommitted National Movement, which represents about 750,000 people who voted uncommitted in the Democratic primaries. A large number of them voted that way to protest Biden’s firm support for Israel amid the Gaza war.

The Harris campaign granted the activists a brief rope line greeting with Harris and vice-presidential nominee Tim Walz; meetings between senior campaign officials and uncommitted delegate leaders; “vigil” space at the convention; and a panel about Gaza off the main stage, which featured pro-Palestinian voices.

But the refusal to provide a main-stage speaking slot, confirmed after the third night of the convention had already begun, was a major rebuff, uncommitted leaders said. One group, Muslim Women for Harris-Walz, said it had “disbanded” because of the decision.

“The family of the Israeli Hostage that was on the stage tonight has shown more empathy towards Palestinian Americans and Palestinians than our candidate or the DNC has,” the group said in a statement.

It is unclear whether the dispute will die down or flare up as the nearly 4,000 delegates at the convention look ahead to Harris’s acceptance speech Thursday night as a culminating high point of the gathering. The pro-Palestinian protests at the convention have been smaller than organizers predicted, in part because activists view Harris as more sympathetic than Biden.

But the broader question of how the Harris team navigates the volatile issue of Israel’s conduct of the Gaza war could persist through the campaign, especially if Israel and Hamas fail to reach a cease-fire agreement before Election Day.

Communication between the Harris campaign and the uncommitted movement is continuing at the convention, including talks about setting up additional meetings, but the conversation about a speaking slot will not be reopened, people familiar with the discussions said, speaking on the condition of anonymity to discuss internal dynamics.

Several speakers on the main stage, including Ocasio-Cortez and Sen. Bernie Sanders (I-Vt.), have mentioned Gaza and called for a cease-fire. Harris’s team has not said whether she will address the war during her acceptance speech, something that could send a signal to the pro-Palestinian activists as well as the party more broadly.

Michael Scherer contributed to this report.