US Election: Democratic presidential candidate Joe Biden picks California Senator Kamala Harris as running mate

Democratic presidential candidate, Joe Biden, has selected California Senator Kamala Harris as his running mate.

If Biden wins the US presidential race in the November 3 election, Harris will take the role as Vice President.

Harris, 55, has become the first black woman on a major presidential ticket in US history.

"I have the great honor to announce that I’ve picked @KamalaHarris - a fearless fighter for the little guy, and one of the country’s finest public servants - as my running mate," Biden announced on Twitter on Wednesday morning (NZ time).

In Harris - a California Senator who made her own bid for the White House before endorsing Biden - the Democratic candidate has gained an experienced politician already battle-tested by the rigors of the 2020 presidential campaign as they head into the final stretch, Reuters reports.

Harris, a former prosecutor who also served as a state attorney general in California, will be relied on to help drive the African-American vote. Four years ago, the first dip in black voter turnout in 20 years contributed to Democrat Hillary Clinton's upset loss to Donald Trump.

Biden, whose floundering campaign was rescued by the African-American vote in South Carolina's primary in February, needs their strong support to oust Trump from the White House.

The black vote will be crucial in battleground states such as Michigan, Pennsylvania and Wisconsin, states the President won by the slimmest margins in 2016 - but now, Trump is trailing his Democratic rival, according to opinion polls. It is also central to Biden's hopes of winning Southern states Georgia and Florida - states Trump carried four years ago, but current opinion polls indicate will be competitive this election.

Biden served as Vice President for eight years under President Barack Obama, the United States' first black President.

As a presidential candidate, Harris took Biden to task in a nationally-televised debate regarding his past stances on mandatory busing for students as a means to desegregate schools. Some Biden advisers have told Reuters the attacks made them question whether she would be a trusted working partner, due to her political ambitions.

While that exchange failed to boost her White House hopes, the Biden campaign will now look for her to train her prosecutorial fire on Trump and Vice President Mike Pence. Harris is scheduled to debate Pence on October 7 in Salt Lake City, Utah.

If elected, Biden - who will turn 78 in November - will be the oldest person to become President. Biden's age has led to speculation he will serve only one term if elected, making Harris a potential top contender for the nomination in 2024. Some allies have reportedly expressed concerns that possibility alone would make Harris a bad fit as Biden's number two, questioning her loyalty.

Biden publicly committed to choosing a woman as his running mate in a March debate after discussing the matter with his wife, Jill. He had considered other former presidential rivals, such as Senators Amy Klobuchar and Elizabeth Warren.

Following the widespread social unrest that erupted over the alleged murder of unarmed African-American man George Floyd by a white policeman in Minneapolis, Biden's search focused predominantly on candidates of colour.

As reported by Reuters, Biden considered several African-American women for the role in addition to Harris, including former Obama administration national security adviser Susan Rice, Atlanta Mayor Keisha Lance Bottoms and US Representative Val Demings, a former police chief in Orlando, Florida. Biden also considered Asian-American Senator Tammy Duckworth and New Mexico Governor Michelle Lujan Grisham, a Latina.

In the aftermath of Floyd's alleged murder, Harris became a prominent voice in the push for racial justice and police reform, standing in solidarity with marchers and sparring with Republicans in the US Senate over reform legislation.

Harris will be confirmed as Biden's running mate at the Democratic convention that begins on Monday, where Biden will also be formally nominated to challenge Trump.

Brian Brokaw, a California political consultant who managed Harris' campaigns for attorney general and Senate, described Harris as "someone who can really make Republicans quake in their boots". 

Reuters / Newshub.