There is no such thing as left leaning or right leaning.
There will be turnout models that differ. They may differ to result in varied results, but they are all making a call about turnout.
Some may use the Census to define D/R/I party mix in turnout, and they make their 1000+ phone calls and toss out respondents if they already have enough D or R or I. The Census defined that, not the pollster, and the Census is 2021, quite old now. But other pollsters may use a different source of D/R/I. Maybe actual checking of Secy of State sites for states — and of course that will run into problems with the several states who do not register by party.
When pollsters hire spokespeople from both sides, you will get interpretation text that is slanted, but the data itself derives from turnout model. If they expect extra black turnout because of Harris, if they expect extra women turnout because of Harris, these are not unreasonable expectations. They may be wrong, but not unreasonable.
Which is why these polls are pretty tightly clustered. None are coming in with 15 point leads in both directions. They are almost all within MOE.
Oh and btw, national results vs battlegrounds.
Calif and NY have huge leads with huge populations. The big Trump population states of TX and FL do not have huge leads. Huge as in 20+%. NY and Calif will show that while TX and FL do not.
This does mean that 2-3% national lead likely points to a battleground Trump victory. There are claims, just a few floating around out that, that Trump’s improvement in CA and NY lessen this effect and one cannot rely on 2-3% being an Electoral College win.
My own personal examination of the latest CA and NY results does not support this presumption of Trump improvement in those states. They do not look different from 2020’s numbers, at least not outside MOE. But note there are few NY or CA polls. Nobody has put money into that.
There are also more 3rd party people in those states this year vs 2020. To my surprise the actual 2020 Wiki results for NY say only about 1% of the vote went anywhere other than Biden or Trump. That means nobody else was on the ballot.
Well... I get that you want to quibble over words, and "lean left" is not strictly scientific.
However, in 2020, 17 of 20 pollsters tracked by Real Clear Politics (RCP) overestimated Biden's vote percentage -- the worst of them, including CNN and Quinnipiac, by over 7%.
People naturally see this as "leaning left" and can even accuse such pollsters of conducting "push polls" hoping to influence the election with their skewed polls.
But another way of looking at it is that Biden hugely underperformed what some pollsters expected, meaning the worst of them were calling for Biden to receive nearly 6 million more votes than he actually did.
Chose your own perspective on that.
In 2020, only three of 20 pollsters came close to the actual results -- Insider Advantage, Susquehanna and Trafalgar -- and they all "leaned right", meaning they predicted a much closer popular vote.
The fourth closest was Rasmussen, and they "leaned left" predicting a slightly larger Biden win than the actual turned out to be.
In the 2022 midterms, everything changed, with most of the top 2020 pollsters -- i.e., Insider Advantage, Rasmussen, Trafalgar -- sliding to the bottom and some of the worst in 2020 -- CNN, FOX, NYTimes -- rising to the top in 2022.
Also, overall, the margins of error were about 1/3 less in 2022 than in 2020, so they all adjusted and came closer to actual.
And returning to the pattern of 2018, in 2022, half the errors were "right leaning", and some were exactly neutral -- CNN, NYTimes & CBS.
So, what will happen in 2024?
I think it's worth noticing that the error pattern of "left leaning" vs. "right leaning" in 2020 was almost identical to the previous presidential election, in 2016, suggesting something happens when Trump is on the ballot which doesn't happen when he's not.
Have all the pollsters made the correct adjustments in 2024, to give us more reliable predictions?
Maybe, but there's no way to know for sure until after the election in November.
Electoral college math suggests that Harris needs more than +3% in the popular vote to win the electoral college and as of today, only five pollsters show Harris ahead by more than +3%:
Take your pick.
Owen: "Which is why these polls are pretty tightly clustered.
None are coming in with 15 point leads in both directions.
They are almost all within MOE."
The spread from Harris +6% to Trump +3% is nine points.