There is no verified evidence from credible sources that the shooter of Charlie Kirk was a Democrat or liberal, despite some rhetoric pushing that claim.
There is a campaign of people pushing the rhetoric that Charlie’s Kirk shooter was a democrat and liberal.

‘Despicable’: Republicans and Democrats condemn violence after Charlie Kirk killing | Charlie Kirk shooting | The Guardian
Source: theguardian.com
Key Evidence
FBI Director Kash Patel confirmed the investigation and manhunt are ongoing with no confirmed suspect identity.
abcnews.go.comabcnews.go.comManhunt for shooter continues after Charlie Kirk killed in 'political...
Major news outlets report bipartisan condemnation but do not confirm shooter’s political affiliation.
pbs.orgpbs.orgConservative activist Charlie Kirk dies after being shot at Utah Valley...
theguardian.comtheguardian.com‘Despicable’: Republicans and Democrats condemn violence after Charlie Kirk...
Trump and others blamed 'radical left' rhetoric generally but did not provide evidence linking the shooter to any party.
theguardian.comtheguardian.comCharlie Kirk shooting death
theguardian.comtheguardian.comCharlie Kirk shooting: Trump blames ‘radical left’, but does not mention attacks...
What the Evidence Shows
Based on the available information from multiple reputable news outlets, the identity and motives of the shooter who killed Charlie Kirk remain unconfirmed as of now. The FBI is still conducting a manhunt and investigation.abcnews.go.comabcnews.go.comManhunt for shooter continues after Charlie Kirk killed in 'political... None of the major reports from ABC News, PBS, The Guardian, The New York Times, or other sources provide verified details about the shooter's political affiliation.
While some political figures and commentators have blamed 'radical left' rhetoric broadly, this is a political framing rather than confirmed fact about the shooter’s identity. The suspect was reportedly taken into custody and then released by the FBI, which further complicates any definitive claims about their background. The media coverage emphasizes bipartisan condemnation of the violence without confirming partisan details about the perpetrator.pbs.orgpbs.orgConservative activist Charlie Kirk dies after being shot at Utah Valley...
theguardian.comtheguardian.com‘Despicable’: Republicans and Democrats condemn violence after Charlie Kirk...+4 more
Therefore, claims that there is a coordinated campaign pushing the narrative that the shooter was a Democrat or liberal appear to be politically motivated rhetoric rather than factually supported at this time.