"They will double down. Any opportunity to hurt Trump, and that is the reality," Trump Jr. said.
"Democrats and media hate Trump much more than they love America because you can't dispute the numbers. You can't dispute all-time low unemployment for every group in this country, every demographic."
Trump Jr. also suggested that any Republicans who only vote to hear from Democrat-request witnesses "don't deserve to be in office."
"If some of those guys don't want to hear from the witnesses we'd want to hear from but will hear from the others, I want to know about it, because they don't deserve to be in office."