Biden's poll lead over Trump could narrow with a successful vaccine, Morgan Stanley says

President Donald Trump gestures to the crowd of supporters during a campaign rally at the Allen County War Memorial Coliseum in Fort Wayne, Indiana, Nov. 5, 2018.
Carlos Barria | Reuters

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The announcement of a successful coronavirus vaccine before the 2020 election could narrow Joe Biden's poll lead over President Donald Trump, Morgan Stanley told its clients Wednesday.

A vaccine would not only allow the Trump campaign to refocus the public's attention on improving economic data, but also offer investors a reason to brush off potential infection resurgences in the interim.