Shootall, I'm not a lawyer but I think it's the other way. The constitution give the Feds certain, limited powers but retains most of the powers to the states. The Feds adjudicates problems between the states and regulates commerce between the states and represents the states to foreign governments. HOWEVER, since the Civil War, the Federal government has assumed more and more control both intra and inter state through direct intervention and manipulation.
A simple example is the withholding of "federal highway funds" if a state doesn't comply with federal affirmative action quotas. If a local jurisdiction "thinks" a felon "might" have crossed state lines, the FBI is more than willing to charge in and take control of a investigation. Or to "assist" a local jurisdiction like at Waco or Ruby Ridge.