Just as the saying goes that generals are always fighting the last war, politicos are always running the last campaign. And as we look to 2020, that means Democrats waging a war against the Electoral College. If only we elected presidents by popular vote, the argument goes, Hillary Clinton would be president now and Donald Trump would be marketing hotel rooms and selling overpriced steaks. Or something like that.

The discussion has centered on fairness: “I voted for Hillary and she won the popular vote but she’s not president so my vote didn’t count and I am disrespected” is the mantra of the blame-game era. That discussion ignores the real blame game; as in, we won popular vote but lost the election, so we have to fix that part.

Elizabeth Warren has called for abolishing the Electoral College, and other 2020 candidates have expressed support. A group has gotten 14 states plus the District of Columbia to pass legislation that would require their Electoral College electors to vote for the national popular vote winner if that is different from who won their states. (More on that below.) Those who want to electoral vote to be abolished in favor of a popular nationwide vote have thrown around the term “minority vote dilution” as one of the main reasons for doing so.

But the reasoning is getting muddled by ideologists talking about civil rights and unfairness and part of the cultural war both sides are pushing right now. It actually has more to do with urban America being left out of the process these days, as the big cities—like New York and Los Angeles and Chicago—don’t really count because the states they are in are not in the small group of swing states that decide who is president.

And what is funny about all this is that the one person who sees that reasoning behind this fundamental switch in how the nation counts votes is Trump himself. “The brilliance of the Electoral College is that you must go to many States to win. With the Popular Vote, you go to … just the large States – the Cities would end up running the Country,” the president tweeted in mid-March. “Smaller States & the entire Midwest would end up losing all power – & we can’t let that happen. I used to like the idea of the Popular Vote, but now realize the Electoral College is far better for the U.S.A.”

As usual, he is right in some respects, and very wrong in others.

The movement to get rid of the Electoral College has popped up from time to time historically, and this latest effort is largely seen as a long shot. Abolishing the Electoral College outright would require a constitutional amendment, and it’s unlikely that smaller (and usually redder) states are going to sign on to something they see as benefitting urban voters in blue coastal states.

Still, Sen Brian Schatz (D-Hawaii) introduced a conditional amendment in Congress this week to abolish the Electoral College. He said in a statement that “the person who gets the most votes should win” and that the current system is “outdated” and “undemocratic.” Though it has support of many Democrats in both the house and the Senate, it is along shot at best.

However, the National Popular Vote Interstate Compact is making an end run. It has proposed a process without a constitutional amendment to move to the individual vote count within the framework of the Electoral College. States will still determine how their own electoral votes are awarded, but state legislatures can pass measures dictating that their electors go to the winner of the national popular vote rather than the candidate who wins their state.

Hence the National Popular Vote Compact, cited above. The group figures that if enough states to go by popular vote and hit the 270 electoral number, they can then get the popular vote to win out. Large states like California and New York and Illinois are among the 14 states (plus D.C.) that have signed on—and there are a total of 189 electoral votes in that group. They are now fishing around for 81 more votes, and they will need red states to do that. And so the likelihood of this happening to affect the 2020 election is quite uncertain (In Ohio, they are trying to get a state constitutional amendment on the ballot in November to do this.)

But if the scenario plays out, it would have a profound effect on campaign strategies. Any big change like this has winners and losers, and in this time of political polarization, there will be many who legitimately fall into one of those categories, and certainly many more who say they do.

What the data gatherers and the campaigners tell me is that the political game under an “individual vote counts” presidential election will be so different that it will take several elections to figure things out. Swing states will no longer be a thing, big cities will be more in play, and smaller state populations less so. Turnout will still be the highly-desired and ever-elusive golden calf, and the candidates will have to switch gears on ideology much more than they do now to achieve that.

And then there is the spending, particularly on advertising.

“I think moving from an Electoral College vote to a direct popular vote would have huge and enormous implications on how they advertise and organize their campaigns during the election,” says Zachary Peskowitz, a political science professor at Emory University in Atlanta and who has studied and has written extensively about presidential voting behavior.

“The presidential campaigns will be advertising in every in every media market in the country, have field offices in every city, and that will be enormously different,” he says. “The policy positions will be different too, because right now, they are only concerned with a certain number of battleground states, and the rest of the country doesn’t really count.”

Think of it this way. Of the top 20 metro markets in the U.S., only six —Philadelphia, Miami, Tampa, Denver, Detroit and Boston—had any big ad buys by either the Trump or Clinton campaigns (or the PACS with them) during the last six weeks of 2016. And the Boston ad buys were a bit of an anomaly, because the commercials weren’t for Boston itself, but for Maine and New Hampshire voters contained in that larger media market.

There is a lot of data that shows how Clinton outspent Trump 75 percent to 25 percent ($410 million to $160 million by best estimates). But most of it was very swing-state centric (Pennsylvania, Florida, Ohio etc.). She got more than 60 percent of the vote in 10 metro areas (nine of which were in the top 15 markets), but advertised in only a few of them because they weren’t in swing states. Trump, on the other hand, got more than 50 percent of the vote in 10 metro areas, but all were ranked 22nd (Charlotte, N.C.) or below. None of these markets showed up on his ad spending radar either, largely because most of those smaller urban metros weren’t in swing states either.

Before we get into the data, let’s get the uncertainty of this speculation out of the way. Yes, each presidential election is different. And yes, how media will be used for candidate messaging will likely make some markets more influential and others less so. Lastly, turnout matters the most and is hard to predict, and elections always turn on who shows up to vote and who doesn’t. No one ever can figure that out in advance.

But, again, to simplify things, the top five major urban markets—New York, Los Angeles, Chicago, Dallas/Fort Worth and Houston—will be players in this new game as opposed to being unimportant in the current system. That is the basis for how things will change; big cities will become the swing states.

Right now, most of the top 20 metro markets get hardly any political attention during the campaign even though about 40 percent of the U.S. population lives in those areas. And even though about 47 million American citizens have Hispanic heritage, there has been little public push for their vote, because they live mostly in states not in play. Furthermore, issues like big urban infrastructure needs and renewable energy development get pushed to the side because the parties don’t think those issues will matter much with the suburban or rural populace.

If you follow the arrows here, it is obvious where the major changes move if this Electoral College elimination goes through. First, urban areas will become where the national race is decided, meaning that winning Minneapolis/St. Paul and Phoenix will matter more than winning Minnesota or Arizona. Secondly, the Latino vote will have much more importance, given that, of the top 10 states in foreign born population, only Florida is ever truly in play. And lastly, issues like affordable housing, global warming, immigration and entitlement spending will be more discussed within these more left-leaning urban parts of the country.

“I think minorities will get more attention, and that will focus both on policy and turnout,” says Michael Franz, director of the Wesleyan Media Project and associate professor of government and legal studies at Bowdoin College in Brunswick, Maine. “You really might see candidates getting into specific issues related to certain parts of the country, because they will be able to secure those votes—and those votes will count nationally—by pairing those voters with specific messages.”

“And the ground game will be even more important, because every one of these metro areas will matter, instead of just a few,” Franz adds. That means, he says, more political decision-making will come from the big cities, instead of from the political party hierarchies in the state capitals as is done now.

To say such a change distinctly favors one party or another, however, is hard to figure in some respects. Metro TV markets can be huge and diversified; New York City has about 30 counties in four states in its media market, and trying to buy one commercial on the late night TV news that hits with balance in those diverse populations is difficult. And expensive.

“Whether we think it is ‘fair’ would only be one of the inputs to the political compromise, although evidence would probably suggest it would be less important to you than whether a change would benefit your preferred political party,” says Gary King, a Harvard University American political scientist and quantitative methodologist. “It is hard to figure out whether it would benefit one side or the other since once you change the rules, as all the parties and candidates and voters will adjust their strategies.”

Multiple changes to the ways of doing presidential campaign business are indeed a certainty if we change to a popular vote. Some of those adjustments, Trump already did. He proved that well-chosen “micro-targeting” ad buys and rally locations upended conventional thinking — and basically worked. He also figured early on that the old tactics of too much reliance of billboards, mailings, TV ads, and big group endorsements (like union approvals) were overblown.

Going into big markets for priority campaigning will be like exchanging seven swing states for 50 metro markets. If the more specific demographic and economic message profiling can be done more effectively, under the individual vote system, it would be possible to hit right-leaning, middle-ground voters in a metro areas that overall might be considered more left-leaning and “green new deal” favoring areas. And the opposite as well.

In other words, the parties can hit who they want to hit if they think about their audience a little differently than under the current system

Take Nashville, Tennessee, where Trump took about 56 percent of the metro area’s vote. There are about 2 million people in the area, but it’s split between red and blue. More immigrants are moving there, and polls have shown voters favoring allowing illegal immigrants to stay in the country under certain circumstances. But the city recently rejected a mass transit funding plan, as conservatives wanted more roads and less rail and buses.

But it’s not a place that presidential candidates are campaigning in, because the state is not in play. It is not so much how the scorecard is being tabulated that makes this interesting; it is that, remarkably enough, the Nashville area voters are really not thought to be part of the national election right now.

The story is similar nationwide. Those top 20 metro areas, with about 40 percent of the national population, accounted for about 36.7 million votes in the 2016 election (based upon age-eligibility, citizenry, registration and the average national turnout being about 60 percent). There were about 129 million who voted nationally for either Trump and Clinton. A majority would be roughly 65 million.

So, under the individual vote counting system, let’s figure that one candidate takes 60 percent of this 20-market urban vote, and the opponent takes 40 percent. If the candidate gets 60 percent of this top 20 population market vote, that is worth 35 percent of the popular vote needed to win. If the turnout goes up by 5 percent the candidate gets 38 percent of the votes needed to win. Go up to 70 percent and they have 41 percent of the vote.

Expand that to the top 50 urban markets—all with a metro populations of more than 1 million—and a presidential candidate can get 57 percent of the votes needed to win with the 60/40 split and higher turnout.

That is a big change, getting about almost 60 percent of the votes needed to win from cities that mostly don’t count now. Only about 6.7 million people that voted in those top 20 urban areas really counted in 2016 (Miami, Philadelphia, Detroit, Tampa, and Denver), which means about 30 million voters didn’t.

And that is what intrigues the campaign consultants. Lots of voters really don’t count now, aren’t used to being courted, but will be looked at as having value if this change is made. The key question is how to get to them? Easy.

Those top 20 city media markets have about 49 million “TV homes” in them, according to Nielsen Media Research. That would be about 43 percent of the TVs in play nationwide.

New York City, Los Angeles, and Chicago have 14 percent of those TV homes. So even putting just them in the mix would have huge import. Adding 50 more “swing cities” means an even bigger play.

So start cranking the ads. Because, as acclaimed media theorist Marshall McLuhan once said, “The medium is the message.” Only in this case, perhaps, “The medium gets a message.”