Even before the coronavirus pandemic hit the US in the spring, very little about former vice president Joe Biden's campaign was conventional. "I am a gaffe machine," he said last December before waging a behind-the-scenes general election campaign against Donald Trump in 2020. Mr Biden, often referred to as Uncle Joe, has been in the public eye since the early 1970s as a senator from Delaware and then as vice president for two terms alongside former president Barack Obama. Throughout, Mr Biden’s family tragedies, losing his wife and their daughter in 1972 and then a son in 2015, has defined a large part of his image with voters and created personal connection over loss and grieving. As a candidate in six campaigns for the US Senate and three for the Presidential nomination, Mr Biden is known for his loose talk. Whether it was his claim in 2008 that you should have a "slight Indian accent" when visiting Dunkin Donuts, or when he wrongly assumed the mother of an Irish leader was dead in 2010, the Democratic nominee's list of gaffes runs long and is often followed by apologies. But the verbal mishaps that accompanied Mr Biden for almost five decades in politics appear to be controlled as he wages the most important campaign of his life to defeat Mr Trump and win the presidency on November 3. The lack of gaffes is largely in part because Mr Biden is running most of his campaign from his home in Delaware, with a minimum amount of public visibility and very little in-person engagement. From the pandemic in March until Memorial Day on May 25, Mr Biden relied strictly on online campaigning, phone calls and tele-rallies. By contrast, Mr Trump was promising a return to stadium rallies and clashed with the governor of North Carolina for putting in place health guidelines for the Republican convention that has now been cancelled. John Zogby, the head of polling company Zogby Strategies, says Mr Biden's strategy is simply to let Mr Trump run against himself. “Joe Biden is playing it wisely by allowing Trump to run against himself, and staying a bit behind the scenes has helped him,” Mr Zogby said. “Being in his basement is not a problem because we [the public] have adjusted to all these changes. We can’t expect campaign rallies and knocking on doors.” Mr Biden himself is seeing value in his minimalist strategy. His poll numbers are improving and is leading nationally by an average of nine points, compared with the three points Hillary Clinton led by at this stage of the campaign in 2016. "The more that Donald Trump is out, the worse he does. I think it is wonderful that he goes out," Mr Biden said jokingly in an online event with Asian American and Pacific Islander voters this month. Another distinction from the 2016 campaign for Democrats is Mr Biden and his campaign have led the effort to unify the party ranks between the centrist and leftist groups before the party's convention on August 17. A <em>New York Times</em> poll from early July showed that an overwhelming majority of primary supporters of former progressive candidates Bernie Sanders and Elizabeth Warren are now behind Mr Biden. The Sanders and the Biden campaigns issued a joint platform laying out an approach to health care, climate change, criminal justice, the economy, education and immigration. But, with 100 days left until the election, Mr Biden has yet to pick his running mate and a lot could change. Never in recent US election history has the vice presidential pick carried as much attention and intrigue as is the case today with Mr Biden. If he wins in November, Mr Biden, who will be 78 by the time he is sworn in, would be the oldest president to take office, making it uncertain that he would seek a second term in 2024. The leading candidates for the VP position are US senators Ms Warren, Kamala Harris, Tammy Duckworth, Congresswoman Karen Bass and former national security adviser Susan Rice. The Trump campaign has been having trouble defining and attacking Mr Biden and could shift the attacks to his No 2. Election observers expect the polls to narrow as the race enters its final three months. But Mr Biden is not taking any chances and is advising his followers on Twitter to “ignore the polls and register to vote".