They needed someone who could woo disaffected members of the President's base and a candidate who could rebuild the old Blue Wall of Michigan, Wisconsin and Pennsylvania. They turned to a son of Scranton, Pennsylvania, who became a senator and vice-president, Joe Biden.
Trump wants to reclaim the Blue Wall he snuck through by 80,000 votes in 2016. Biden has been trying to patch up any cracks and scars still left with frequent visits to the former Democratic states in the past month. Win Clinton's states and those three and Biden will be the next president with 270 Electoral College votes.
Biden is ahead in the FiveThirtyEight.com national polling average by 8.6 points and is leading in state averages for those three key battlegrounds plus the Republican-held Arizona, Florida, Georgia and North Carolina. Trump has small leads in Ohio, Texas and Iowa.
And that's after more than 95 million people have voted early - 70 per cent of the 2016 total votes.
Strengths and weaknesses:
With his experience and name recognition, Biden always looked like a likely Democratic nominee, even when in the primaries he presented himself as mainly a return to normality. The pandemic, economic fallout, climate crisis and Black Lives Matter protests mean he now has to be a transformative president, should he be elected.
Biden, at 77, would be the oldest president ever, but he has been able to present himself as the mirror opposite of Trump. The precise way his campaign has handled coronavirus-safe rallies and speeches, compiled a policy platform with input from former primary rivals, and been strategically smart, suggests they know what they're doing.
Biden doesn't inspire the same devotion among Democrats as Trump does among core Republicans, but he doesn't have to. Democrats, some independents and renegade Republicans are fired up to tell Trump 'you're fired'. The type of motivation doesn't matter.
They are united now, but should Biden win that could change once he is actually in charge and starts filling out an administration. Different factions will want a seat at the table.
His advantages:
If you are facing an incumbent, it pays if people are already used to you in a similar role. It doesn't take much of a leap to imagine you in the top job. After two terms as vice-president, for Biden it is barely a step. It also means he has connections with a host of policy experts to serve as advisers. Biden's long-time persona as a moderate has been problematic for Trump. Trying to present him as a radical or 'puppet of socialists' doesn't work. At the same time, Biden can present quite bold policy plans without losing his pragmatic tag.
His campaign:
Biden has essentially allowed Trump to dig his own holes, such as the President's focus on the Hunter Biden allegations and media fights, rather than issues that matter to the electorate such as the pandemic, the economy and healthcare. Trump needs to draw in more independents to pad out his support, and none of that helps.
According to polling, Biden has been on the right side of all the most import issues in terms of who would be best to handle them, apart from the economy where Trump has an edge.
The new surge in coronavirus cases, which is particularly hurting people in Republican-run states in the middle of the country, is a brutal rejection of Trump's claims that the outbreak is improving.
Biden is able to grab the contrast he is actively seeking: Reality over surreal spin, responsibility over irresponsibility, concern over indifference, competence over incompetence, unity over division, respect over spite.
What the polling data says:
Biden has his own coalition. Biden has been less strong in polling with African Americans and Hispanics than Hillary Clinton but appears to be making up for it with more white voters - the biggest voting bloc. There is a larger gender gap between the two candidates than in 2016. Suburban women, who were a major part of the Democratic success in the 2018 Midterms, are still with the party against Trump. Biden leads with both young voters and senior citizens in polling. Gen X is the one age group which prefers Trump.
CNN political analyst Ron Brownstein, an expert on the demographic changes occurring in US regions, commenting on Washington Post poll data on Sunday tweeted: "The consistency of Biden's coalition across all the Rustbelt states is striking: 3/4 or more of non-white voters, 55%+ w/college whites (here 59) & slight gain to around 40% of non-college whites. That's his Biden coalition in MI/WI/PA & if he holds those 3 states he's won."
Verdict:
Despite his polling advantages, Biden will need one or two clear signposts to victory on election day and a landslide overall to avoid a dragged out denouement with Trump, who has much to lose legally should he be defeated. Those signs could come from North Carolina or Florida, which are both on the east coast and count election results quickly. Trump needs both to win.
This is Biden's election to lose.