Early-state Democratic voters say President Trump's allegations against Joe Biden have not affected their views of Biden and largely think they aren't true. Even so, it's Elizabeth Warren who continues to draw support from Democrats. She has extended the aggregate lead she had in this poll last month across the 18 early primary and caucus states.

As for individual states, she has increased her lead over the pack in New Hampshire and pulled even with Biden in Iowa. And Warren leads in our delegate model over Biden, too, demonstrating that she's competitive in many regions.

However, it's Biden's response to the president, not the charges, that may be more telling here: more Democrats say Biden's response has left them somewhat satisfied than very satisfied.

Meanwhile, Warren is seen as generally better able than Biden to handle the inevitable political attacks from Mr. Trump in the 2020 presidential campaign, with more Democrats saying they believe Warren would handle any attacks "very well" than saying the same of Biden.

Warren is the first choice of voters who say that having an "inspiring" candidate is very important. She narrowly leads Biden among those who say being "tough" is very important; and — seeming to cut into one of Biden's key arguments — is about even with him among those who say being "experienced" is very important.

Warren and Bernie Sanders both outpace Biden by more than 20 points on being seen as a candidate who will "fight" a great deal for people like them.

And an important backdrop to all this: for Democrats deciding how to vote in these states, a candidate's position on impeachment is not the most important issue. In fact, it ranks far behind issues like health care, climate change, income inequality and guns. This echoes something Democratic voters have voiced since the summer: they have long told us they would rather hear candidates talk about beating Donald Trump in 2020 than about impeaching him.

With the top tier of candidates at least 70 years of age, the poll asked this month, as it did last month, whether candidate age was a concern for voters. Once again most say it is not. But more voters now say Sanders, who is 78 years of age, is too old. We followed up and asked why. Among those who feel Sanders is too old, more than eight in 10 worry his age would make it difficult for him to do the work required of the presidency. By comparison, among those who feel Biden is too old, more feel concern that he would be "out of touch."

And on the electability front, long a prized trait among Democrats: among those considering Warren, a 56% majority continue to think she would probably beat Mr. Trump, similar to last month. Those considering Biden still rate his chances higher, but that number has dropped. Among those considering Biden, two-thirds think he'd probably beat Mr. Trump. Last month, 77% of those considering him at the time believed he would.

In a campaign that's been heavily focused on policy debates, one important split among voters may be in what they believe is achievable. Most of Biden's supporters consider Warren's policy proposals to be "idealistic" and consider those of Biden, whom they back, as being "realistic." But Warren's supporters overwhelmingly think her proposals are realistic. One difference between Warren and Sanders is that among Democrats, more see Warren's plans as realistic, while a majority describe Sanders' plans as "idealistic."

Warren does as well as Biden in support among those looking for a candidate who would compromise to get things done, and better than he does among those looking for someone who sticks to principles and sets big goals. Warren's continued growth has drawn support from previous Biden and Sanders backers among those re-interviewed, so it is not strictly a battle between her and Sanders on the progressive side of the party. For all three, most current supporters say they're strongly in support, particularly those backing Sanders.

In Iowa, we see an especially fluid race, and as Warren has gained, so has Pete Buttigieg: he's up from last month, though still in fourth place. Both Biden and Sanders have slipped there. In South Carolina, Biden continues to lead — now the only one of those early three states where he still does — helped by strong support from African-American voters.

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This CBS News survey was conducted by YouGov between October 3 and 11, 2019. A representative sample of 16,500 registered voters was selected in 18 states expected to hold early primaries and caucuses (Alabama, Arkansas, California, Colorado, Iowa, Maine, Massachusetts, Minnesota, Nevada, New Hampshire, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, Utah, Vermont, Virginia). This sample includes 7,958 self-identiﬁed Democrats and Democratic-leaning Independents. This sample was weighted according to gender, age, race, and education based on the American Community Survey, conducted by the U.S. Bureau of the Census, as well as 2016 presidential vote. The margin of error is +/- 1.6 percentage points.

All early states

Iowa

New Hampshire

South Carolina