After weeks of feverish speculation and intensive lobbying, presumptive Democratic presidential nominee Joe Biden will name his running mate over the next seven days.

The 77-year-old has missed two self-imposed deadlines to announce his pick but will finally do so before the Democratic National Convention, which runs from August 17 to 20, begins.

Biden has pledged to name a woman, and is under pressure to pick someone of color who will appeal to progressive and young voters, can be an effective governing partner, has the experience and competence to do the top job, and offers some generational balance.

The virtual campaign also changes the considerations – perhaps a great campaigner is less important – and while whoever is selected will be targeted by Donald Trump and the Republicans, the former vice president will be wary of picking anyone who rocks the boat given his substantial polling lead.

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History suggests the choice of running mate has little impact on the way people vote – other than a small home-state bounce or if a bad call is made – but given Biden's age, the growing movement for racial justice and the dire economic situation likely to be inherited if victorious, 2020 could be a little different. 

Here are the names believed to be in the frame:

Kamala Harris (55)

The California senator ticks many boxes and has long been considered Biden's most likely choice, but some in the former vice president's camp have expressed reservations. 

Strengths: National experience with strong name recognition, an effective media performer who would balance the ticket in terms of ethnicity – her mother emigrated from India, her father from Jamaica – to a degree ideology – her Senate voting record is liberal, but not to the extent that scares moderates – and age.

Weaknesses: A bid for the Democratic nomination which didn't catch on with voters and a record as a prosecutor regarded skeptically by progressives. While Biden looks to have put her attack on him in the first Democratic debate behind him, his wife Jill described it as a "punch to the gut" and adviser Chris Dodd has questioned her lack of "remorse" over the incident.

Susan Rice (55)

President Barack Obama's national security adviser and ambassador to the UN is the only top tier candidate who has extensive experience of working with Biden. 

Strengths: Experienced African American woman who holds the credentials to step into the top job, and would represent continuity for those looking for a third Obama term. She helped create the White House pandemic-preparedness office that Trump closed, and was influential in the U.S. support of the Paris climate accords and the Iran nuclear deal. Knows the ins and outs of international relations and has a reputation for competence.

Weaknesses: Never run for political office and hasn't faced the scrutiny of a political campaign, reputation damaged by her handling of the aftermath of the Benghazi killings and lack of appeal to progressives. Her views on domestic policy are largely unknown and on foreign policy are not popular with the Bernie Sanders wing of the party. The Washington insider is a multimillionaire, whose holdings may prove controversial with liberals. 

Gretchen Whitmer (48)

The Michigan governor visited Biden at his Delaware home last weekend, and shortly afterwards made a series of announcements on racial inequality. 

Strengths: High-profile governor of a key swing state and thought to be close to Biden. She gave the Democratic response to Trump's state of the union this year and has repeatedly locked horns with the president, who dismissed her as "that woman from Michigan," over the COVID-19 pandemic.

Weaknesses: Embarking on a vice presidential run at a time her state is recovering from a crisis could be a risky move, especially if Michigan were to be hit with a second COVID-19 wave in September or October. Though she is a popular governor, there are questions over her accomplishments since taking office in 2019. 

Karen Bass (66)

The California congresswoman and head of the Congressional Black Caucus is far from a household name, but thanks to her work on racial justice was catapulted into the top tier of candidates following the death of George Floyd. 

Strengths: Accomplished legislator who appeals to progressives. In the House of Representatives she has pushed for police reform, and as speaker of the California State Assembly she helped shape the state's recovery efforts after the 2008 financial crisis. She has the credentials to be an effective partner for Biden without overshadowing him. 

Weaknesses: Low national profile and little scrutiny of her record – until now. Republicans have found plenty of fodder for attacks ads, including past comments about Cuba and scientology that have caused controversy.  

Elizabeth Warren (71)

The Massachusetts senator and former Harvard Law School professor is a leading light in Democratic progressive politics, but as an older white woman may not offer the diversity some in the party are hoping for. 

Strengths: Warren was an effective fundraiser and the standout debater – destroying Michael Bloomberg's candidacy – during the Democratic nomination process, but struggled at the polls. She is experienced, a household name and her liberal credentials would appeal to progressives. She could be a unity candidate for the party, and has consistently got under the skin of Trump. 

Weaknesses: Despite a strong endorsement of Biden, they haven't always had the best of relationships and her economic populism hasn't been embraced across the party. Age is also a potential problem – she's younger than Biden, but still a septuagenarian. Her Senate seat in Massachusetts would be filled by an appointee from a Republican governor, off-putting in a year the Democrats hope to win back the chamber.

Tammy Duckworth (52)

The Thai-American senator for Illinois and former U.S. Army lieutenant colonel would be the first female veteran on a national ticket.

Strengths: An inspirational personal story: She lost both her legs and partial use of an arm when her helicopter was shot down during the Iraq War, and, aged 50, was the first sitting senator to give birth. She is a moderate who has focused her legislative work on veterans and people with disabilities, and could have strong appeal in the Midwest and with veterans. 

Weaknesses: Hasn't been strongly vetted on the national stage, doesn't hold much policy appeal to progressives and has had little to say on big issues of the day like the economy and race.

Other names in the frame

Tammy Baldwin: The first openly gay senator when elected in the key swing state of Wisconsin in 2012, the 58-year-old could appeal to both Midwestern and progressive voters. But, like Warren, her seat in the Senate may be judged too valuable to risk in a special election.

Keisha Lance Bottoms: The Atlanta mayor has increased her national profile with a strong response to the COVID-19 pandemic and embrace of the racial justice movement. The 50-year-old has been a strong supporter of Biden throughout his candidacy and comes from a state Democrats dream of flipping, but picking a mayor with limited experience would be a big call.

Val Demings: The Florida representative and former Orlando police chief is from a key swing state and has serious law and order credentials. The 63-year-old was also one of the House managers during the Trump impeachment trial, but her time in the police force has come under scrutiny.

Michelle Lujan Grisham: The only non-white female governor in the United States – she has executive experience in New Mexico, performed effectively during the pandemic and as a 60-year-old Latina would give the ticket balance in terms of race and age.

Kyrsten Sinema: The Arizona senator represents a seat the Democrats want to flip, and the small home-state bounce the 44-year-old may deliver puts her in the mix.

The process of picking a running mate has been unusual under Biden, in that there has been regular public discussion of it by the candidate. But despite the comparative transparency, few people really know what the former vice president is thinking. 

Stacey Abrams has been effectively ruled out by pundits, for example, but remains a popular figure in the Democratic Party. It's possible Biden may yet make a leftfield choice.