When somebody becomes a front runner often the idea of said person being nominated or be elected frightens and wakes up people.
In 2016 for the Dems and progressives the idea that Trump would be elected President was just beyond their comprehension so this phenomenon did not happen.
Up until recently Bernie did not frighten "mainstream" democrats and their mainstream media mouthpieces, they thought he is a kind of entertaining codger. But after Bernie's Nevada blowout it was OMG we are going to nominate a SOCIALIST, OMG he is going to take my Cadillac health insurance away, OMG he praised the Soviet Union while honeymooning there, and said a few nice things about Castro and the Contras to boot, OMG the "Bernie Bros" are misogynist extremists, a left wing version of the "MAGAS", all information readily available to anybody who did not want to ignore it.
Now that Biden is the front-runner people will realize "Joe being Joe" looks a lot like senility. The question is will enough people realize it in time (or is too late already)? The "Never Trump" conservatives were too little, too late in 2016. The Democrats who spent the last 4 years criticizing Republicans for jumping on the Trump train are coalescing around Biden faster than the Republicans did around Trump.
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Professionally Identified and joined WP August 26, 2013
DSM 5: Autism Spectrum Disorder, DSM IV: Aspergers Moderate Severity
It is Autism Acceptance Month
“My autism is not a superpower. It also isn’t some kind of god-forsaken, endless fountain of suffering inflicted on my family. It’s just part of who I am as a person”. - Sara Luterman