Bernie Sanders zeros in on Joe Biden as his favorite foil

Bernie Sanders is quick to slam Joe Biden’s past support of free trade deals and the Iraq War. He is warning him against a “middle ground” approach to addressing climate change. His campaign sends fundraising appeals with a simple, foreboding subject line: “Joe Biden.”

In his nearly three weeks as a presidential candidate, Biden has become Sanders’ favorite foil.

No one seeking the 2020 Democratic presidential nomination has been as aggressive as the Vermont senator in highlighting episodes from the former vice president’s past to sow skepticism in the party’s progressive base.

The strategy is reminiscent of Sanders' apporach to the 2016 Democratic primary, when he relentlessly slammed Hillary Clinton as an establishment pawn. And it's a reminder that, even when Sanders lags in the polls, he is often most comfortable when he's taking on top Democrats, hoping that such attacks will energize his most loyal supporters