Trump and Vance are expected to attend Kirk's memorial service

Organizers said they expected to fill State Farm Stadium in Glendale, which has a capacity of more than 73,000 spectators, and had prepared additional space if there were more people in the nearby arena, said a spokesman for Kirk's activist group Turning Point USA, according to Reuters.

Security will be heavy, given that President Trump will be in attendance, and due to the ongoing political turmoil following Kirk's death. A senior security official told Reuters that the event was assigned the highest level of security for events of "highest national importance".

Kirk, 31, was killed on September 10 during a rally on the University of Utah campus. The 22-year-old, who has been charged with murder, told his partner in a text message that he killed Kirk because he had "had enough of his hatred".

Kirk's killing raised fears of a growing incidence of American political violence across the ideological spectrum and deepened partisan divisions.

Trump, who is a close ally of Kirk, criticized the killing and stepped up calls for action against his political opponents, including left-wing organizations he blamed for the gun attack even though authorities said the gunman acted alone.

Kimmel's show canceled

The uproar over Kirk's killing intensified last week when ABC abruptly canceled longtime host and comedian Jimmy Kimmel's show after conservatives expressed outrage over Kimmel's comments about Kirk's murder.

ABC's decision came just hours after Trump's Federal Communications Commission chief, Brendan Carr, threatened to use his agency to punish the network over Kimmel's comments.

Kimmel's suspension drew opposition from civil rights groups, Democrats and both television and film writers, who say the Trump administration is using Kirk's death as a pretext to stifle critical media in violation of the US Constitution's First Amendment protection of free speech.

Pete Hegseth, Marco Rubio and Robert Kennedy are also in attendance

The list of speakers at today's Kirk memorial, titled "Building a Legacy: Remembering Charlie Kirk," shows Kirk's influence as the leader of the nation's largest conservative youth organization, Reuters writes.

In addition to Trump and Vance, who was personally close to Kirk, senior administration officials including Secretary of State Marco Rubio, Defense Secretary Pete Hegseth and Health Secretary Robert Kennedy will speak.

Kirk's widow Erica, who was elected director of Kirk's organization Turning Point last week, is also scheduled to speak.

In his address, Trump intends to portray Kirk as a martyr who sacrificed himself for the conservative movement and promote his legacy as a cultural and political force, one White House source said.

He is expected to use the moment to draw a line between Kirk's death and what he says is left-wing extremism. The source declined to say whether the US president would call on supporters to remain calm, or whether his tone would be unifying or combative.

Kirk, who has built a large following through his deft use of social media, radio shows and campus tours where he often invites skeptical students to debate him, is credited with mobilizing young voters to vote for Trump in 2024.