The sad orange sack of shit is bragging about the Rasmussen Poll like anyone's ever heard it before. The reason why no one (other than conservatives) put stock into the Rasmussen Poll is because it's has proven to be the least accurate of the political polls with an average error of ~6% and Republican lean of ~4%. That, and it's heavily skewed to favor today's Republican politician.
Of course Trump would troll the internet to find a survey with numbers he likes. A more reliable indicator is likely the RealClearPolitics Average, which has him at 39 percent (actually up slightly from some craters in late summer and November). The Gallup Poll has him at 35 percent, which sounds about right.