Want to see who'll play key roles in setting energy and environment policies in the next administration? Then look closely at who is advising the presidential candidates, Sens. Barack Obama and John McCain. Obama, an Illinois Democrat, has a notably deep bench of experts to help him answer key questions on energy prices, oil drilling and global warming. His advisers on those issues outnumber those of his Republican rival by more than 3 to 1. By contrast, McCain's campaign relies on a small group of longtime friends and advisers.