Activists and advocacy groups are staging a second round of “No Kings” protests across the country on Saturday in response to what they call abuse of power by President Donald Trump and his administration, including his immigration crackdown.

Organizers predict millions will take part.

Republicans are trying to brand the protests as “hate America” rallies and claim they’re prolonging the federal government shutdown.

Here’s what to know.

What are the “No Kings” protests?

The daylong “No Kings” protests set for Oct. 18 follow up on the thousands held in mid-June. They are being run by a coalition of organizations including the American Civil Liberties Union, Indivisible, 50501 and others. Organizers say there are more than 2,600 events planned nationwide — including major cities such as New York; Washington, D.C.; Chicago and Los Angeles — and say millions are expected to attend.

They have been “organized by regular people, by volunteers,” Deirdre Schifeling, chief political and advocacy officer of the ACLU, told ABC News.

While organizers have not released details on fundraising ahead of the protests, and the coalition has remained relatively decentralized, a few groups have indicated either heavy spending to promote the rallies or planned star power to increase buzz around them. 

For instance, Home of the Brave, a political group, said Monday it was spending $1 million to advertise the No Kings protests, including in local and national newspapers.

Celebrities, including Jane Fonda, Kerry Washington, John Legend, Alan Cumming and John Leguizamo, are slated to attend, according to a fundraising email on Thursday from the political action committee Progressive Change Campaign Committee.

“We’ll be in the streets for immigrant families under attack and for voters who are being silenced. For communities being terrorized by militarized policing. For families who are about to lose their health insurance. And for every single person whose rights are threatened by this administration’s cruelty,” the group wrote in the email.

In advance of Saturday’s rallies, law enforcement is actively monitoring social media and the internet, as well as working with local organizers and potential counter-protesters, to get a sense of what might be expected. That vigilance comes as there continues to be heightened concerns about large-scale public gatherings, especially political events.

What are Republicans saying about the protests?

Republicans have been slamming the protests, claiming that the protests are a reason the Democratic Party does not want to end the ongoing federal government shutdown.

Senate Majority Leader John Thune asserted on Wednesday that Democrats are waiting to solve the funding issues until after Saturday’s “No Kings” rallies.

“The truth is — what Democrats really want is something Republicans can’t give them. And that is the approval of their far-left base,” Thune said. 

Republican leaders have also framed the “No Kings” protests as a series of “Hate America” rallies, framing the upcoming events as meant to criticize America and what it stands for.

“And I encourage you to watch — we call it the ‘Hate America Rally’ that will happen Saturday,” House Speaker Mike Johnson told reporters on Wednesday. “Let’s see who shows up for that. I bet you see pro-Hamas supporters. I bet you see Antifa types. I bet you see the Marxists in full display, the people who don’t want to stand and defend the foundational truths of this republic.”

Johnson did not provide any proof to support his claims that “pro-Hamas supporters” and “Antifa types” will show up. Organizers have said they cannot control who shows up to protests from outside groups and have emphasized wanting to keep protests respectful and nonviolent.

In an interview taped with Fox News’ Maria Bartiromo on Thursday, Trump was asked about the rallies and he shot down that he was a “king.”

“They’re referring to me as a king. I’m not a king,” Trump said. 

Some state leaders have also said they are calling up more law enforcement in light of the protests, which supporters of the protests have said may be meant to “suppress” them.

Texas Gov. Greg Abbott, a Republican, wrote on X on Thursday, that he “directed the Dept. of Public Safety and National Guard to surge forces into Austin” ahead of the rallies.

“Texas will NOT tolerate chaos. Anyone destroying property or committing acts of violence will be swiftly arrested,” Abbott wrote.

State Rep. Gene Wu, who chairs the state House’s Democratic caucus, wrote in response, “Sending armed soldiers to suppress peaceful protests is what kings and dictators do — and Greg Abbott just proved he’s one of them.”

How are protest organizers responding to Republican claims?

Organizers have countered that Republicans in power are responsible for the ongoing shutdown, and have said that Johnson and some other Republicans not saying the name of the protest is telling.

“I think it’s really telling that he spent an entire week calling this a ‘hate American Rally,’ on the attack against this coalition and Americans across the country, and he won’t even say the name of the protest,” Leah Greenberg, co-executive director of Indivisible, one of the major groups in the “No Kings” coalition, told reporters on a press call on Thursday. 

“That’s because if you say the name of the protest, ‘No Kings,’ the entire argument falls apart … there is nothing more American than saying that we don’t have kings and exercising our right to peaceful protest,” Greenberg said.

When asked if they thought the claims from Republicans would impact participant turnout on Saturday, organizers said they think it could have the opposite effect.

“I think, if anything, it will increase turnout,” said Schifeling. “I think Americans can really see through these sad attempts to distract attention from the failure of these Republican Congress people and Republican Trump administration to actually address what most Americans want and need from their government.”

Ezra Levin, the co-executive director of Indivisible, told ABC News that he welcomes the publicity, but simultaneously believes Republicans are trying to stop Americans from exercising their First Amendment right.

“I think the Republicans and Trump see that the largest peaceful protest in modern American history is coming together on Saturday to push back against the authoritarian overreach by this regime and its supporters in Congress, and they’re looking for ways to message against it ahead of time,” he said.

ABC News’ Josh Margolin contributed to this report.