To become the presidential nominee, a candidate typically has to win a majority of delegates. This usually happens through the party's state primaries and caucuses. Learn more about state presidential primaries and caucuses and how delegates are chosen for the national convention. State delegates go to the national convention to confirm their choice of candidates by casting votes. But if no candidate gets the majority of a party's delegates during the primaries and caucuses, convention delegates choose the nominee. This happens through additional rounds of voting. At the convention, the presidential nominee officially announces who will run with them for vice president.