2016 was not a head to head race. In the end their margin was R+5 relative to the actual results if you poll the race that actually existed (four candidates), and more specifically as I've pointed out polls with the winner at 46% are useless. Clinton was underpolled by 1% and Trump by 6%.
PPP has a horrible D bias but even here if you want to give them the same error as 2016, Biden would win 50-49.
PPP is indeed a democratic polling outfit, but i r c there in House lien for Democrats in polling results is negligible.
