In practice , the presidential nominee has considerable influence on the decision , and in the 20th century it became customary for that person to select a preferred running mate , who is then nominated and accepted by the convention . In recent years , with the presidential nomination usually being a foregone conclusion as the result of the primary process , the selection of a vice presidential candidate is often announced prior to the actual balloting for the presidential candidate , and sometimes before the beginning of the convention itself . The first presidential aspirant to announce his selection for vice president before the beginning of the convention was Ronald Reagan who , prior to the 1976 Republican National Convention announced that Richard Schweiker would be his running mate . Reagan 's supporters then sought to amend the convention rules so that Gerald R. Ford would be required to name his vice presidential running mate in advance as well . The proposal was defeated , and Reagan did not receive the nomination in 1976 . Often , the presidential nominee will name a vice presidential candidate who will bring geographic or ideological balance to the ticket or appeal to a particular constituency
1976 Republican National Convention
1976 Republican National Convention
Vice President of the United States