Lloyd Green at The Guardian:
Joe Biden sits squarely atop an unwieldy Democratic presidential field, and is the only challenger who appears comfortably competitive when paired against Donald Trump in electoral battlegrounds such as Michigan, New Hampshire and Wisconsin. While other contenders lead the president in national polls, Biden is the one candidate who generates the kind of coalition necessary to avoid the debacle of 2016, that is a Democratic popular vote victory coupled with another electoral college defeat.
Biden is reassuring, not strident, and in that sense he is the anti-Trump. Barack Obama’s vice-president runs well with traditional Democratic constituencies along with those swing voters necessary to cobble together a win on election day 2020.
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Trump is unpopular but that does not make a Democratic victory a given. Unalloyed progressive economics tethered to full-throated multiculturalism could cost them the White House. It is a reality that many Democrats understand and intuit. That is why the numbers show Biden leading the primary field. Electability is a real thing.