is "the mayor himself spoke to the crowd" intensive or reflexive

Intensive and reflexive pronouns are very similar, they have the same form: myself, yourself, himself/herself/ itself, ourselves, yourselves (plural), themselves; but their functions in a sentence differ.

Reflexive pronouns are used when the subject and object are the same.

You can help yourself to dress – correct
You can help you to dress – incorrect

Intensive pronouns are used to add emphasis to the subject or antecedent of the sentence. Usually, an intensive pronoun is right after the noun or pronoun it’s modifying.

Who threw the garbage?” “I did it myself.”

Important to know: intensive pronouns aren’t essential to a sentence, you can omit it, but reflexive pronouns are important for a sentence's meaning.

As for our sentence - The mayor himself spoke to the crowd.

If we remove the pronoun himself, does the sentence still make sense?

Yes, it would keep its meaning and needed information - The mayor spoke to the crowd.

Therefore, 'himself' is an intensive pronoun in this sentence.