This below is the 2020 consensus, there are swing states, leaning states, among others on a spectrum and in terms of support, one does need to think not about medians but about majorities. How many states will your favored candidate win. Note that bad actors (including the Russians) will do what they did in 2016 and more, targeting for the margins that ensure victory for a giant screaming yam.
After the Democrats’ suburban dominance and the GOP’s rural success in the 2018 elections, members of both parties say they think the Republican strongholds of Arizona and Georgia will come more into play in 2020, while the swing states of Ohio and Iowa are increasingly turning red.
And there’s general agreement that at the outset of the 2020 contest, three historically Democratic-leaning midwestern states President Donald Trump flipped in 2016 — Michigan, Pennsylvania and Wisconsin — along with the perennial battleground of Florida will be at the core of the fight.
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Democrats are encouraged about their prospects in the upper Midwest after sweeping the 2018 Senate and gubernatorial races in Michigan, Pennsylvania and Wisconsin. If all other states vote the same way as 2016, but Democrats bring those three states back into the fold in 2020, they would eclipse the 270 electoral votes necessary to win.
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Even with the possibility of new states entering the playing field, Democrats are determined not to repeat the mistakes of 2016, when Hillary Clinton tried to expand the map in Arizona, Georgia and Texas at the expense of locking down critical midwestern states.
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Democrats are also well aware that their 2018 victories will not guarantee success when Trump is back on the ballot. In the 2010 midterms, Republicans won the Senate and gubernatorial elections in Iowa, Pennsylvania, Ohio and Wisconsin, as well as the governor’s race in Michigan. Obama went on to carry all five states two years later.
www.mcclatchydc.com/… (2018)
This 2017 state-level example demonstrates how much work needs to be done