A manifesto is a public statement stating your views or your intention to do something. If you feel you should be voted "Most Likely to Succeed," you could issue a manifesto describing all the reasons why you deserve to win.
Manifesto comes from the Italian word of the same spelling, meaning "public declaration explaining past actions and announcing the motive for forthcoming ones." You'll most often hear about a manifesto that's been issued by a group, like a political party or government — for example, a set of new rules that an incoming regime is going to enforce. Though organizations are more likely to create a manifesto, it's also possible for an individual to issue one about more personal ideas.