Sanders backers mock, attack Biden over his speech impediment

Remember when Donald Trump mocked a reporter over his disability, arthrogryposis, a congenital condition affecting the joints? A 2016 poll of likely voters picked that slight over the hundreds of others committed by Trump as his worst of that campaign.

Enter supporters of Democratic primary challenger Bernie Sanders. If you are on Facebook or Twitter, you have likely come across some Internet quacks who claim the speaking gaffes committed by Democratic presidential front runner Joe Biden are due to dementia and cognitive…