US Vice President Kamala Harris said Wednesday she was "scared as heck" that Donald Trump would return to the White House in the November election and urged Democrats to "fight back."

Her comments came after Trump won on Monday in the Iowa caucuses, the first step in the Republican nomination race to challenge President Joe Biden later this year.

"I am scared as heck, which is why I'm traveling our country... we should all be scared," she told The View show on the ABC network.

But the 59-year-old Harris added, "We don't run away from something when we're scared, we fight back against it."

Harris was responding to a question about reports former president Barack Obama was concerned with the Biden campaign, and to comments by ex-first lady Michelle Obama saying she was "terrified" of a second Trump term.

According to a recent ABC News/Ipsos survey, Trump leads his Republican opponents in key popularity indicators as the 2024 primary season begins, while Biden's job approval rating has dipped to the lowest rating for any president in the last 15 years.

A DailyMail/J.L Partners poll also revealed that six in ten people, including almost one-third of Democrats, believe Biden should not run for president in 2024.

Biden has stepped up direct attacks on Trump recently, warning that the twice-impeached former president -- who faces 91 criminal indictments -- poses a threat to "US democracy".

A recent poll measuring Harris' popularity among Americans revealed that the Vice President's approval rating dropped by over 5% since January, going from 41.7% to 36.3%. Another poll analysis showed lower approvals, as 55% of voters disapproved of Harris' term, making her critically more unfavorable than Biden, who himself holds a record for being the least approved US president. 

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