If Wolverine can hold his own against Hulk then he could definitely hold his own agains Blob (and possibly even win).
Hulk could definitely kick Blob's ass. No problem.
Spider-Man is pretty strong and he's way too fast for Blob to touch him so yeah I think all three characters could take Blob one-on-one.
Wolverine can't hurt him... MAYBE minor scratches but they heal up very quick due to his healing factor.
Spiderman can't even phase him. His hits are as nothing and he can rip his webbing by just flexing his fat and muscle.
Hulk IS the biggest challenge here but Hulk has been KOed before. Now that Blob is in the 70ton range he can KO Hulk too. Maybe Hulk KO's himself if he gets angry enough and bounces off.
All three at the same time is kinda tough. Who knows.