The problem with this polling is that they tend to co-mingle the results nationwide. It may be true that in the aggregate, the Democrats are ahead by 12 points. But when you remember that we have 435 different races, the “wipeout” may not exist. Out here in the Bay Area, I don’t think there are ANY Republicans running for the 7 or 8 seats in the November ballot. So, of course, the polling here would show 100%-0% for the Dems, since there’s nobody on the other side, generic or not.
This is also why the polls in 2016 were so bad. The 5 million illegal votes that Hillary got in California meant nothing. She got the 55 Electoral votes whether she won by 5,000,000 or 537 votes.
But the LIV out there don’t realize this, so they believe these silly polls and may wake up on November 7th “horrified” that the Republicans still hold both the House and the Senate.
There are districts in LA, Philadelphia, Boston and NY that go 95% Democrat. Most Republican districts in flyover country are 55/45. The 12% number is meaningless.