Sen. Bernie Sanders (I-VT) ended his presidential campaign last week, therefore making former Vice President Joe Biden the Democratic Party’s unofficial nominee. Mr. Biden, still 766 bound delegate votes away from clinching a first ballot victory is now unencumbered in his bid to become the party standard bearer. It is likely that he will secure the 1,991 bound first ballot delegate votes once the June 2 primary, now featuring ten states, is held.

Sen. Sanders conceded that he could not overcome Mr. Biden’s strong lead but stopped short of endorsing him though it is clear that he eventually will and called for the Democratic Party to pull together in order to defeat President Donald Trump.

How will a Trump-Biden general election campaign unfold? Very likely, the race will come down to what happens in about ten states. In 2016, President Trump defeated Hillary Clinton with an Electoral College margin of 306-232, giving him a 36-vote cushion against Mr. Biden. This is a relatively substantial margin, but when remembering that three critical states containing 46 electoral votes came down to an aggregate vote spread of just over 77,000 votes, such a gap could quickly dissipate.

To win again, President Trump must keep intact five states that he carried as part of his 2016 coalition, three of which are giving signs of moving closer to the political center since the last election, and two that are always in the swing category. Arizona, Texas, and Georgia are must-wins for the Trump campaign, but these states are no longer locks for the Republican nominee. Though they should still remain part of the 2020 Trump coalition, they cannot be taken for granted.

Florida and North Carolina are always swing states, and any Republican presidential nominee must carry them in order to win the national election. The Democrats, because they win most of the other big states, can claim a national victory without Florida and North Carolina but a Republican cannot.

Assuming Trump is victorious in these five states, then he needs to only carry one of the three Great Lakes states that he clinched in 2016. Should Mr. Biden prevail in one of the five core Republican coalition states of Arizona, Texas, Georgia, North Carolina, or Florida, he will almost assuredly win the national election, hence their utmost importance in determining the eventual outcome.

For Mr. Biden to unseat President Trump, and assuming the latter man does hold his five key states, the map becomes more difficult for the new Democratic nominee designate. Again, we turn to the Great Lakes, an area from which Mr. Biden was raised and where he considers his political base. In order for him to overcome Trump’s advantage, the former Vice President and Delaware Senator would be forced to capture all three of the key entities, Pennsylvania, Michigan, and Wisconsin.

Mr. Biden could still claim 270 electoral votes even if he were to fail in Wisconsin, however. Taking the two swing congressional districts from the states that split their electoral votes, Maine and Nebraska, the former VP could win the Presidency by at least scoring plurality victories in ME-2 and NE-2, so long as he holds Pennsylvania and Michigan.

In Maine and Nebraska, a candidate is awarded two electoral votes for winning the statewide vote and one each for every congressional district carried. In 2008, then-Senator Barack Obama won the 2nd District of Nebraska giving him one extra electoral vote. Four years ago, President Trump prevailed in the 2nd District of Maine giving him one extra national vote.

One state that was in the swing category in the past few elections that looks to be discernibly in the Trump column is Ohio. In the past few elections, including 2018, Ohio has been moving to the right whereas several others, as in the case of Arizona, Texas, and Georgia appear to be moving leftward. Assuming this trend continues, Ohio will likely get less attention from the Democrats in 2020.

While obviously all 50 states contribute to the electoral vote contingency to put one of the candidates over the 270-vote national threshold, it appears, unless the paradigm changes, that the result in ten states will determine if President Trump is re-elected or Mr. Biden unseats him. Therefore, we can count on seeing most of the political action and financial expenditures occur in these ten places.

With Sen. Sanders finally yielding, the general election is now, at least unofficially, underway, and it’s onto November.