Obama has an obligation to come out and speak in defense of the First Amendment. If necessary, he should he evoke his favorite, an Executive Order that states if anyone interferes with anyone renting a venue for political speeches is interfered with by individuals protesting the speech should be removed and arrested for violating a person's right to speak.
That would ensure that the protesters are kept outside of the hall where the candidate is speaking and any organization that encourages shutting down of an event, obtaining tickets and not attending the venue or encourages violence at these venues be arrested and held until the speaking engagement is over.
At the same time, any organization that partakes in shutting down of an event be prosecuted for violating another's right to Free Speech, and heavily fined for encouraging forcibly trying to censure someone from using their first amendment rights.
That would ensure that the protesters are kept outside of the hall where the candidate is speaking and any organization that encourages shutting down of an event, obtaining tickets and not attending the venue or encourages violence at these venues be arrested and held until the speaking engagement is over.
At the same time, any organization that partakes in shutting down of an event be prosecuted for violating another's right to Free Speech, and heavily fined for encouraging forcibly trying to censure someone from using their first amendment rights.