Biden opens up national lead.
A Fox News poll shows Joe Biden leading Donald Trump in the presidential race by 12 points nationally, 50% to 38%.
Key finding: Biden supporters are far more likely to say fear that Trump might win is behind their vote choice (63 percent) than to say it is enthusiasm for Biden (31 percent). The opposite is true among those backing Trump, as almost twice as many of his supporters say enthusiasm is the motivation (62 percent) rather than fear Biden could win (33 percent).
Fear is a big factor when it comes to turnout, and that could help Biden.
