Blob is a match for collosus, and he defeated all of the early blue and yellow first generation x-men single handedly. He is super strong, and can change the density of his body at will. As long as he's standing nothing can move him, not even juggernaut, or the hulk. But i didn't say nething bout the ground he stands on.
If Kingpin's using his mass resources and flunkies, then he takes it. In a straight fight, Blob with ease. They said most of the reasons. Another one of his powers is that he can increase the gravity right under him, pretty much sticking his feet to the ground. However, if someone's strong enough to move him, he's taking that part of the ground with him. Also, Blob's body is extremely resilient to injury, absorbing impacts from bullets, missiles, energy blasts, etc. And, Blob is strong enough to tangle with most strong guys in Marvel. For Kingpin to go against something like that on his own is suicide. He's no where his level. He's a freakishly large and extremely strong human, but still just a human.
(f.y.i. Blob's the only legitimate fat one of the two😉)