In picking Kamala Harris, Joe Biden has answered one major question – but raised several more

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With his selection of Senator Kamala Harris as his running mate, former vice-president Joe Biden has answered one major question. He also has raised several more.

In an effort to defeat an incumbent president without precedent, Mr. Biden made a choice that breaks all precedent. Ms. Harris – a 55-year-old daughter of immigrants and a graduate of Westmount High School in Quebec – would be the country’s first female, first Black and first Asian-American vice president.

But before that, Ms. Harris – whose mother was born in India and whose father was born in Jamaica – is the test case in perhaps the biggest unknowns in the 2020 campaign.

Can she become the advance guard in the effort to mobilize the female voters who helped the Democrats win control of the House of Representatives in 2018 but who found Hillary Clinton too off-putting in the 2016 presidential election?

Can Ms. Harris, who in polls during her presidential race never placed higher among Black people than Mr. Biden or Bernie Sanders, stoke turnout among this voting group, which rallied in great numbers to vote for Barack Obama but whose turnout declined by 1.5 million voters when Ms. Clinton was the nominee? This is a vital question in the swing states with large Black urban populations that voted for Donald Trump in 2016: Ohio (Cleveland), Pennsylvania (Philadelphia), Michigan (Detroit) and Wisconsin (Milwaukee).

Biden announces California Senator Kamala Harris as running mate in historic nomination

Can the California senator play a decisive role in swinging key Southern states to the Democrats? The latest Zogby poll puts Mr. Biden ahead of Mr. Trump by four percentage points in North Carolina, which has voted Democratic only twice since 1968; Mr. Obama’s victory there in 2008 came with a surge of Black voters that overcame the 65 per cent of white voters who sided with GOP nominee John McCain. Also potentially in play is Georgia, which has voted Democratic only three times since 1964 but where the unsuccessful Democratic gubernatorial campaign of a Black woman, Stacey Abrams, swelled Black turnout two years ago.

Can Ms. Harris explain her reluctance as California attorney-general to intervene in police killings in Oakland and San Francisco, a reluctance that raised questions after the killing of Michael Brown in Ferguson, Mo., in 2014 and of George Floyd earlier this year? Police violence is likely to be a major issue in the fall campaign, and the Democratic vice-presidential nominee will be called upon to reconcile her strong rhetoric in Washington with her record in California.

With a lead going into the conventions, Mr. Biden did not have to make a selection that would revive or turbocharge his campaign; he merely had to keep his momentum flowing. In any case, the effect of vice-presidential candidates has always been muted. Some of the marquee choices – the Democratic Senator Edmund Muskie (1968), Republican former representative Jack Kemp (1996) – had virtually no impact on the final campaign result. Both men’s tickets lost.

When the political scientists Boris Heersink of Fordham University and Brenton D. Peterson of the University of Virginia examined vice-presidential impact in a 2016 paper, they found that the choice of a running mate could have changed (but didn’t) four presidential elections since 1960. Their study of elections between 1884 and 2012 suggest that running mates boosted their tickets’ vote harvest in their home states by an average of 2.67 percentage points. With different running mates, they argued, the Democrats could have defeated George W. Bush in both 2000 and 2004, and the Republicans could have defeated John F. Kennedy in 1960 and Jimmy Carter 16 years later.

That is one effect Ms. Harris will not have. Four years ago, Ms. Clinton carried California by more than 20 percentage points. The composite FiveThirtyEight poll results taken before Ms. Harris was selected showed Mr. Biden with a commanding two-to-one advantage over Mr. Trump in California. Neither candidate will campaign much, if at all, in California after Labour Day.

An often-overlooked element of the selection of a running mate is what that choice says about the outlook of the presidential candidate – a point Mr. Biden made in his announcement Tuesday afternoon.

“You make a lot of important decisions as president,” he said in an e-mail to supporters. “But the first one is who you select to be your vice-president.”

Dwight Eisenhower selected Richard Nixon, a 45-year old senator, in 1952 to give a youthful sheen to the GOP ticket – an impulse that led George H.W. Bush to choose an equally inexperienced running mate, 41-year-old senator Dan Quayle, in 1988. But when Mr. Nixon was the Republican nominee in 1960, he chose a steady hand (Henry Cabot Lodge Jr., a former senator then serving as U.S. ambassador to the United Nations). That impulse also led the younger Mr. Bush to choose Dick Cheney (former White House chief of staff, defence secretary and congressman) as his running mate in 2000.

Almost always, presumptive presidential nominees say they based their selection on their running mate’s plausibility as president – a stretch in the case of Mr. Nixon in 1952 and of governor Sarah Palin in 2008 but surely the case for Mr. Kennedy (he chose Senate majority leader Lyndon B. Johnson in 1960), former governor Ronald Reagan (George H.W. Bush, 1988), governor Michael Dukakis (senator Lloyd Bentsen, 1988), and governor Bill Clinton (senator Al Gore in 1992). Mr. Biden made that argument Tuesday.

However, the key factor may be the one that Mr. Biden neglected to mention but that Los Angeles Mayor Eric Garcetti, co-chair of the Biden selection committee, said on MSNBC’s Morning Joe program last week. He said Mr. Biden hoped for someone with whom he could have “the same relationship he had with Barack Obama.”

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