The TATA box serves as a target for a critical transcription factor, TATA-binding factor II-D (TFIID). This protein gloms onto the TATA box. At the same time another protein, TFIIB, binds to RNA polymerase. Now polymerase latches onto the gene, guided by interactions between TFIID and TFIIB. In other words, the initiation factors guide polymerase to the proper spot on the DNA with high efficiency, enhancing transcriptional activity. (And actually, it’s much more complex than this—there’s a bunch of other proteins involved, not to mention variations in the pattern from gene to gene. But your Old Quantum Butcher’s trying to keep his eye on the ball, here.)
Enhancers are transcription factors that can bind hundreds or even thousands of base pairs upstream of the gene and its promotor! They then interact with other transcription factors bound close to the promoter, causing the DNA to loop around as polymerase binds and initiates transcription.

 

Figure 24. Enhancers and TBF's. Highly simplified (oversimplified, really) model of regulation of certain eukaryotic genes. TATA- binding factors (TFB's) assemble at the promoter, and enhancers bound far upstream or downstream loop around to interact with TFB's and/or polymerase. These interactions facilitate or stabilize binding of polymerase and enhance transcription. Repressors could also bind the DNA and prevent transcription.