By ERIN SCHUMAKER, ABC News

(WASHINGTON) — With Election Day now in the rearview mirror, election workers are focused on tabulating votes and determining winners. Even in non-pandemic years, counting votes takes time and it’s common for races to be undecided, even well after Election Day.

This year, according to the United States Election Project, more than 100 million Americans cast early votes, either on early voting days or using mail-in ballots.

Of the races still being decided, the presidency most notably hangs in the balance, as key states, including Michigan, Wisconsin and Pennsylvania continue to count votes. Down the ballot, key Senate races are similarly still being decided.

Here’s what you need to know as votes are counted and 2020’s races continue to be projected:

Overall: The presidency is still up for grabs

President Donald Trump is projected to take the battleground state of Florida, but Arizona, Wisconsin, Michigan, Pennsylvania and Georgia still hang in the balance as a possibility for former Vice President Joe Biden as of early Wednesday morning.

Undecided swing states:

Georgia: Georgia’s race is not yet projected.
Why not? After issues in Fulton and Gwinnett counties, Deputy Secretary of State Jordan Fuchs told ABC News that Georgia’s two biggest counties were not expected to report final results Tuesday night.

North Carolina: North Carolina’s race is not yet projected.
Why not? North Carolina counts absentee ballots that arrive as late as Nov. 12. North Carolina also requires a sample audit count to ensure the reliability of election results tabulated by a machine, so following the general election, the state board of elections will randomly select precincts, early voting sites and ballots to be counted by hand in each county. The precincts will be audited beginning 11 a.m. Wednesday.

Arizona: Arizona’s race has not yet been projected.

Michigan: Michigan’s race has not yet been projected.
Why not? Michigan still has votes being counted.

Nevada: Nevada’s race has not yet been projected.
Why not? It’s Nevada’s first time sending mail-in ballots to all active registered voters. The state is accepting ballots that arrive by Nov. 10. Nevada’s elections division announced Wednesday morning that no more results will be released until Thursday at 9 a.m. PT (12 p.m. ET).

Pennsylvania: Pennsylvania’s race has not yet been projected.
Why not? Pennsylvania’s three largest counties — which sent out the most absentee ballots to voters, will continue counting their mail-in ballots into Wednesday. Absentee ballots will not be fully counted until Friday at the earliest after deadlocked negotiations between Democratic Gov. Tom Wolf and Republicans who control of the state legislature.

Wisconsin: Wisconsin’s race has not yet been projected.
Why not? Votes are still being counted in the state.

Key Senate races undecided:

Alaska: Sen. Dan Sullivan (R) vs. Dr. Al Gross (I)
Alaska’s Senate race is not yet projected.

Arizona: Sen. Martha McSally (R) vs. Mark Kelly (D)
Arizona’s Senate race is not yet projected.

Georgia: Sen. David Perdue (R) vs. Jon Ossoff (D)
Georgia special election: Sen. Kelly Loeffler (R) vs. Rep. Doug Collins (R) vs. Rev. Raphael Warnock (D)
Georgia’s Senate races have not been projected.

Maine: Sen. Susan Collins (R) vs. Sara Gideon (D)
Maine’s Senate race is not yet projected.

Michigan: Sen. Gary Peters (D) vs. John James (R)
Michigan’s Senate race is not yet projected.

North Carolina: Sen. Thom Tillis (R) vs. Cal Cunningham (D)
North Carolina’s Senate race is not yet projected.

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