Watch the Jumping To Conclusions online guitar lesson by David Hamburger from Essentials: Fingerstyle Blues
To help strengthen your feel for both the melody and the groove, try playing through the tune a couple of different ways. You can leave out the melody, and just concentrate on where the chord hits fall over the steady bass. Then, forget about the chord hits, and just play through the melody, taking care to still place each lick in its rightful spot in the progression. This way of isolating the elements of a tune can actually be more challenging that playing it intact, but it’s a great step to take once you’re ready to start varying the original tune yourself.