Clinton led among women (+13 points), African-Americans (+74), and voters under age 30 (+17).
She was also ahead by 11 points among the one-in-five who have already voted (50-39 pct).
They split the support of whites with a college degree: Trump got 45 pct to Clinton's 42 pct.
Both candidates consolidated their bases, but Clinton outperforms Trump: she gets 90 per cent among Democrats and he gets 85 pct of Republicans, the poll showed.
Some 74 pct of voters said the FBI investigation intoC linton's use of a private email server while she was Secretary of State would not make a difference to their vote, and 4 pct said it makes them more likely to support her.
Yet 21 pct said it makes them less likely to vote for her, including 37 pct of Republicans and 21 pct of independents. Among Democrats, 5 pct said it made them less likely to support Clinton, while 7 pct said it made them more likely.
While both candidates remained unpopular, Clinton's lost her advantage here. Her net negative rating is 13 points (43 favourable vs. 56 unfavourable).
Last week she was underwater by 8. At the same time, Trump's net negative 12 points (43 favourable vs. 55 unfavourable) improved a bit from negative 14 a week ago, the poll showed.
Roughly 15 pct of likely voters dislike both Clinton and Trump.
Most of Clinton'a supporters remain confident in their candidate, as 90 pct think it will be Madame President, down slightly from 93 percent in mid-October.
At the same time, Trump's supporters felt more confident: 69 pct thought he would win, up from 56 pct.
The Fox News Poll was based on landline and cellphone interviews with 1,211 randomly chosen registered voters nationwide.
The survey included results among 1,107 likely voters. The margin of sampling error is plus or minus 2.5 percentage points for results among registered voters and plus or minus 3 points among likely voters.
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