They were once rivals. Rubio is now helping Trump with debate prep CNN 0 75 06.18 10:16 https://www.youtube.com/watch?v=N-pkX8Af1YU + 7 https://www.youtube.com/feeds/videos.xml?channel_id=UCupvZG-5ko_eiXAup… + 6 They were once rivals. Rubio is now helping Trump with debate prep