“Don’t believe the polls,” says the Biden for President organization in an email to supporters today. It is perhaps an odd message coming from the clear leader in numerous surveys of Democratic primary voters. But former Vice President Joe Biden and his team don’t want any potential donor to think they don’t need additional funds. Money aside, there’s a lingering question about the enthusiasm with which Democrats are embracing Mr. Biden. Meanwhile, chief rival Bernie Sanders seems as enthusiastic as ever about his Marxist ideology.

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