He knows exactly what he's doing
I was watching this rally and heard him call out Katy Tur by name. I thought it might be possible that the crowd would harm her:
Just one day after Donald Trump tried to incite his supporters to violence against his opponent Hillary Clinton if she defeats him in the election, it turns out this isn’t the first time Trump has done something like this toward a woman who got under his skin. MSNBC reporter Katy Tur, who has spent more than a year traveling with the Trump campaign, revealed today that the Secret Service had to protect her from Trump’s crowd after he attempted to incite them against her.
While Tur was covering a Trump rally in Mount Pleasant, he took his longtime grudge with her public. He didn’t approve of how she had covered an earlier incident, so he privately demanded that she apologize, which she refused to do. So Trump retaliated by pointing to Tur and saying to the crowd. “What a lie. Katy Tur. What a lie it was. Third. Rate. Reporter. Remember that.”
The crowd of Trump supporters turned so fiercely against Katy Tur that she says the Secret Service had to protect her while she was walking to her car, simply to keep her safe. She’s referring to it as an “extraordinary step.” The agents are specifically tasked with protecting people such as Presidential nominees, and it is in fact rare that they would feel compelled to protect a reporter due to the unsafe situation she’d been placed in by the candidate they’re protecting.
He knows very well what he's doing. He's intimidating people, especially women, into going easy on him by threatening to sic his violent cretins on them. There was no other reason to publicly name her.
His "rigged election" talk is very likely to inspire a few of these crazies to try something.