New #PA Congressional map is pretty much the best one Democrats could have hoped for. At least 2 pickups in neutral environment, likely ability to win 11 in current D+6 environment. Post coming
PA redraw creates map that is almost entirely drawn from scratch. Huge shifts from 2016 plan all over the place. Dems favored to win 9 seats there in almost any national environment. 
(big swings mostly from renumbering, but aggregate differences are clear)
Whereas the current PA map had a mean-median difference of -7% (a bias towards the GOP), the new court-drawn map is much smaller 3% bias.
Since we’re at this point in the generic ballot where we would have predicted ~7 Dem seats in PA, the new map isn’t the enormous boon for Dems that some are making it out to be. A victory? Of course. Less bias? You bet. But a game-changing redraw? Perhaps, but maybe not.
The new map will be rolled into the 2018 forecasting model soon*. New estimates will have larger standard errors, of course, but expect a modest increase in D probability of taking back the House.
*sometime in the future, at a definite point, but unspecified, maybe indifenitely?
*sometime in the future, at a definite point, but unspecified, maybe indifenitely?
OK, the new PA Congressional map is (A) half as biased toward Republicans, (B) still gives them an upside over Pres performance, (C) points to Dems winning 9 seats in Nov (in current environment) (D) creates big upside in small D wave (E) REALLY MESSED UP NUMBERING. LIKE WTH GUYS
#NEW PA court map is about 2 seats nicer to the Democrats. Here are the changes between districts (old %ages matched up with their new numbers): 
My original #PA map tweet was a little optimistic for Dems: 11 seats very unlikely. Instead, here’s the PA forecast under new vs old boundaries: Democrats all but guaranteed 9 seats at the outset, a huge improvement under old map, but dummymandering already had Ds getting 7. 
(be careful interpreting this because we have no earthly idea what incumbents are about to do)
Been seeing takes saying new PA map is a Dem gerrymander. Nope! Still has a 3% bias toward the GOP (per mean-median test). And per my models, Democrats don’t even win a majority of PA’s seats until they win the House popular vote by 16 (SIXTEEN) points.
