Voters in Georgia, Hawaii, Mississippi and Washington will cast ballots today in a lineup of key primary elections. President Joe Biden and former President Donald Trump are their party's likely nominees after dominating their respective Republican and Democratic primaries on Super Tuesday last week. It's widely expected that following these contests today Trump will attain the 1,215 delegates needed to clinch the Republican nomination and Biden will attain the 1,968 delegates required to clinch the Democratic nomination, officially setting up a rematch in November between the two rivals. This will mark the first rematch between a current and a former president since 1892.