Hillary Clinton and Joe Biden are virtually tied for the 2020 Democratic presidential nomination, a new survey polling hypothetical candidates discovered.

Although Clinton said after her 2016 loss that she would not run for president again, rumors have swirled for months that she is once again considering running for the White House. In fact, Clinton has told Democrats that she would enter the contest should she envision a path to victory. Indeed, one Democrat close to Clinton recently revealed that Clinton thinks about a rematch with President Donald Trump "all the time."

The new Harvard-Harris national poll found that Biden leads the Democratic field by a double-digit margin. But when Clinton's name is thrown into the mix, Biden's lead vanishes almost completely.

If Clinton were to enter the race, she and Biden would be virtually tied, the poll found — Biden with 19 percent of support among Democratic voters to Clinton's 18 percent. Sens. Elizabeth Warren (D-Mass.) and Bernie Sanders (I-Vt.) would fall to third and fourth, respectively

However, the same poll also found that Clinton is seen as very unfavorable among American adults, 56 percent to a 37 percent favorable rating.

The poll's results are significant because it exposes the uncertainty being felt among moderate Democrats. While Sanders and Warren solidify support with far-left Democrats, moderates have become increasingly weary of Biden's fitness for the campaign trail, let alone being commander-in-chief.

It is not clear if Clinton will enter the race. She will have to make a decision soon because filing deadlines to be included on the ballot in early primary states are just weeks away.