According to the Atlantic, Mr. Biden wants a united front and to lower the party's angry volume:

Biden is not getting into name-calling, a la President Trump. 

He's not getting into Sanders-style proposals like Medicare for All. 

And he's definitely not getting into crowd sizes. The roughly 6,000 people who stood in the sun waiting for him was less than a third of the crowd that showed up for Kamala Harris at her launch in Oakland in January; less than half the number Sanders drew for his first rally in Brooklyn in February; and a full 3,000 people behind the crowd who stood in a snowstorm to watch Amy Klobuchar give her kick-off speech in February. In the heart of Philadelphia, nearly half a century after he launched his national political career just down the highway in Wilmington, Delaware, Biden had roughly the same number of people who went to Mayor Pete Buttigieg's kick-off rally in South Bend, Indiana, a month ago.

Maybe we can call it Biden's version of a kinder and gentler liberalism.  Maybe Biden thinks he can bring out "the quiet Democrat" who is not watching Rachel Maddow or Chris Cuomo.  Maybe he has polling data that the party is not so far left as the other candidates think it is.

Biden will face a very simple problem.  First, the base is all about hating President Trump.  They want to get President Trump at any cost, including turning the 2020 convention into a total circus.

Eventually, Biden will have to take a position on abortion, the border, and health care.  He can't avoid specifics too much longer.

Finally, his good polls overlook the fact that most Democrats would prefer a so-called "progressive candidate."  In other words, two out of three voters are not supporting Biden.

Enjoy it, Joe.  Yes, enjoy it, because the base that hates President Trump is going to start hating you pretty soon.

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