Trump has the highest favorables but also the highest unfavorables. I’m not conversant enough on polling science to know how to interpret that.
He’s known by 99% of those interviewed, is new to the arena, and is getting thoroughly lambasted in the press.
But lots of those are GOP voters who don’t like Trump because they back another candidate whose parade Trump is raining on. They’ll come around for the general election.
Also, he’s never gonna get more than just a little over 50% of those who vote in the general—but that’s winning.
Also, this is at best polling “registered”, not “likely” voters. Likely voters reliably lean a little more to the GOP than Dems.
Also, Trump is making huge inroads in the infrequent-voter independents and conservative Democrats—so the infrequent voters who will vote if he is the nominee will also be skewed more toward him than the usual GOP candidate.
Finally, once people actually here him speak at length, he wins many over. So it is not surprising that his negatives have fallen—and likely will continue to fall if he becomes the nominee. (And even being named the nominee will give him credibility in his new arena of politics.)