Unsubstantiated claims by President Trump alleging improper business activities in Ukraine and China by Hunter Biden – the son of former Vice President Joe Biden – have failed to knock the elder Biden out of first place in the race for the Democratic presidential nomination, a new Fox News poll shows.

In addition, attacks by the former vice president’s Democratic opponents seeking to portray him as too moderate and too focused on the past have also fallen flat as Democrats compete to face Trump in the 2020 presidential election.

The Fox News poll of likely Democratic primary voters, released Sunday, shows that while Biden fell behind in some state polls, he has solidified his decisive national lead. Biden gets the support of 31 percent of likely Democratic primary voters, with Sen. Elizabeth Warren, D-Mass., trailing with 21 percent.

FOX NEWS POLL: BIDEN LEADS NOMINATION RACE, TOPS TRUMP BY 12 POINTS IN MATCHUP

Sen. Bernie Sanders, I-Vt., who has steadily dropped in most recent polls and was sidelined briefly after suffering a heart attack, came in third at 19 percent. South Bend., Ind., Mayor Pete Buttigieg finished fourth with 7 percent.

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Biden’s consistent support largely comes from the view of most Democrats that he is in the best position to help them achieve their top goal – ending Trump’s tenure as president and telling him, in effect, “You’re fired.”

The poll shows that 80 percent of likely Democratic primary voters say it is extremely important that the party’s nominee can beat Trump in the election one year from now. Of this group, 68 percent believe that Biden can defeat Trump, compared with 57 for Warren, 54 percent for Sanders, and just 30 percent for Buttigieg.

Biden’s significant lead is further substantiated by the RealClear Politics’ latest national average of polls of likely Democratic primary voters, which has Biden garnering 29 percent nationally, Warren at 20 percent, Sanders at 17 percent, Buttigieg at 7 percent, and Sen. Kamala Harris, D-Calif., at 4 percent.

But while Biden enjoys strong support nationally, the state-by-state numbers show his support is eroding in the first states where nominating contests will be held – Iowa and New Hampshire. Coming out on top in the Iowa caucuses and the New Hampshire primary is critically important to Biden, because it would confirm his status as the candidate in the best position to defeat Trump.

The most recent polling in early states reveals a great deal of ambiguity, and indicates that the field of Democratic presidential hopefuls will likely remain competitive throughout the first few months of voting.

In Iowa – where Biden was leading just two weeks ago – he has now slipped into third place, behind Warren and Buttigieg.

“I think we’re the only ones who don’t have to win Iowa, honestly, because our strength is the fact that we have a broad and diverse coalition,” said Biden’s campaign manager, Greg Schultz, indicating that Biden’s campaign is bracing for a loss in the Feb. 3 caucuses.

According to the RealClear Politics average in Iowa, Warren leads the field with 22 percent of the vote and is followed by Buttigieg, who has climbed to second place with 17 percent, while Biden has dropped down to just under 16 percent.

Additionally, Warren holds a narrow 4-point lead with 24 percent of the vote in New Hampshire, and is trailed by Biden and Sanders at 21 percent and 20 percent respectively, according to the RealClear Politics average.

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However, Biden’s momentum recovers in Nevada, where he maintains a 5-point lead, and in South Carolina, where he holds a substantial 20-point lead, according to RealClear Politics averages.

Significantly, most Democratic candidates – including those polling in single digits – hold notable leads over President Trump in general election matchups.

As the Fox News poll released Sunday reveals, Biden holds a considerable 12-point lead over President Trump in a general election matchup. Similarly, Sanders and Warren hold 8-point and 5-point leads over Trump, respectively.

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Despite these candidates’ leads over the president in these early ballot tests, the unpredictability and instability of this primary cycle cannot be ignored.

Ultimately, the volatility in early primary states coupled with the all-consuming impeachment inquiry being conducted by House Democrats both pose serious problems for all top-tier candidates moving forward.

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