After winning the party nomination, candidates from both parties spend much of their time campaigning in a series of state primary and caucus contests, trying to win delegates that will represent them on the national ballot. Candidates also participate in televised debates where voters can question them about their plans and positions.
In the final stretch of this presidential race, both Harris and Trump are attempting to rally voters in key battleground states to support their causes. With early voting about to begin in many states and with Election Day less than seven weeks away, the stakes are high for both sides.
For a number of reasons, the presidential race has been exceptionally close this year. Kamala Harris showed up Mr Trump in their only debate and enjoys a financial advantage, but has struggled to close the gap with the former president. In addition, her political legacy is a liability as she seeks to fend off attacks from the right. She is a creature of institutional politics rather than an ideologue and needs to articulate a clear vision that appeals to voters beyond her base.