It probably is higher. Lots of people have no idea who's on the other end of the line - and don't want to 'come out' as a Trump supporter. People lied to pollsters running up to the time of Trump's election too -- and for good reason.
“52%? Should be higher.”
It would be if it wasn’t for Congress. Ryan and the rest of the GOPe are slow walking and stonewalling Trumps agenda because they know it will work and any chance of getting rid of Trump is gone. Ryan is a lying snake and the last thing he wants is Trump at 60% or higher approval.