The pro-illegal, pro-amnesty republican establishment is keeping Rubio on hot-standby as Jeb’s replacement in the event they cannot reverse the collapse of Jeb’s campaign.
What of significance has Rubio accomplished in his life? He has worked very hard to promote amnesty - was part of Gang of 8. He lied to voters, missed a lot of Senate votes - does not think being a Senator is of any importance, hasn’t exactly handled his own finances well, and is beholden to special interests. He would be a disaster as POTUS. Somebody dubbed him the GOP’s Obama.