Donald Trump has reached a new high in the polls, sending fresh shivers through the Republican establishment’s spine, but those familiar with the nitty-gritty details of the surveys say they harbor plenty of small cracks and flaws that should give rivals hope that the real-estate tycoon isn’t yet running away with the nomination.

Friday’s CNN-ORC International poll showed Trump at 36 percent among self-identified Republicans and GOP-leaning independent voters, up 9 percent since mid-October and 20 points clear of his nearest competitor.

But some Republicans and data journalists urged observers to disregard Friday’s CNN poll. It is a bit of an outlier: A Quinnipiac University poll also released this week showed Trump at 27 percent, only a modest increase since the school’s last survey.

Also to consider: The shaky track record of polls, most recently in the Kentucky governor’s race, in which Matt Bevin bested Jack Conway despite pre-election polling consistently showing Conway with a lead going into the November election.