The Democratic nominee hopes to persuade working-class voters in Ohio and Pennsylvania.
“We are going to tie the Democrat candidates to Hillary Clinton and the failed policies that she supports," the chairman of the network's funding arm said.
Trump called retired Marine Gen. John Allen a “failed general” after the highly respected military veteran delivered a forceful endorsement of his opponent, Hillary Clinton.
Trump also took aim at Clinton directly during the rally Friday, promising to escalate his attacks against her.
The veteran civil-rights activists joined others in defending protesters against criticism that they are divisive.
Clinton and Kaine will campaign across Ohio and Pennsylvania, two key states.
The campaign of the runner-up sent a text message beforehand asking people to be respectful.
"As a medical doctor, there was a time where I looked very closely at those issues, and not all those issues were completely resolved," said Green Party's likely candidate for president.
Trump called Clinton's speaking style "a very average scream."