Do We Really Have A Say In Our Future?

Or is destiny beyond the reach of human influence? In watching the presidential race, it first seemed inevitable that Hillary was going to be presdient. Now there is an air of destiny surrounding Barack Obama. Is our future sealed by the destiny of certain individuals, having nothing to do with stances on positions, or even the voting process? Can we have any effect on outcomes of events such as electons? Let's not forget that even though Al Gore won the popular vote, he did not become president because other forces were at play. Is our future pre-ordained, then, and how can the future be changed?