According to
http://wheresthepartydoc.blogspot.com/2016/11/republicans-winning-house-of.htmlWho is doing a calculation under
https://docs.google.com/spreadsheets/d/1uFj6bHCEKfRN78oiMmVaQWqoyfil6e85qCeZIu1DRnk/edit#gid=0The current Congressional vote share is around GOP 50% Dem 47%. Of course this number has a lot of imperfections. In CA we have a lot of Dem vs Dem runoffs which undercount GOP support. There are a handful of seats where there is no major party opposition to the winning party.
But what is clear is that besides RCP average for Prez vote undercounting GOP (Clinton +3.3% vs something like Clinton +1.5%) the RCP generic Congressional poll average was also off and undercounted GOP (Dem +0.6% vs GOP +3%)
It seems the final Bloomberg poll which had Clinton +3 (not that off in retrospect since it will end up being Clinton +1.5) nailed it with GOP +3 in the generic Congressional ballot. One can make the argument that Bloomberg was the best all around pollster of this election as it also had a poll in FL with Trump +2 which ended up being correct.
In the end the GOP did run ahead of Trump just like many predicted. This seems to imply that if various third parties candidate not run Trump was likely to win anyway and perhaps even win the PV.
