McCain solidifies front - runner status . Clinton takes oil - rich states . Huckabee , Obama vow to keep fighting . Democratic voters remain evenly split over which of their candidates they would rather see get the nomination . Obama taking more states , but Clinton taking states with more oil .
McCain solidifies front - runner status . Clinton takes oil - rich states . Huckabee , Obama vow to keep fighting . Obama taking more states , but Clinton taking states with more oil .