It’s only one poll, and a national poll at that, but PPP says Donald Trump is suffering badly from his loss in Iowa:
“Donald Trump’s really seen some cratering in his support this week,” said Dean Debnam, President of Public Policy Polling. “A key part of his message has always been that he’s a winner and now that he’s lost something Republicans—and especially conservatives—aren’t finding him as compelling as they did a few weeks ago.” [Marco] Rubio is the candidate with the real momentum in the race. He’s up 8 points from his 13% standing in our poll right before Christmas.”
Trump is still a few points ahead in the main polling, but PPP also polled a three-man race between Trump, Rubio, and Ted Cruz. The winner was Rubio. Trump can huff and puff and threaten to sue the entire state of Iowa—in other words, his usual MO—but it’s not going to change things. Live by the polls, die by the polls.