Democrats may be ecstatic that they retook the House of Representatives , but their decisive victory conceals a harsher reality: It took a landslide in the popular vote to get them here, and they are projected to lose seats in the Senate .

Those facts speak to just how far the U.S. election system is tilted in the Republicans favor. Through a combination of fundamental factors and partisan gerrymandering, Republicans on Tuesday retained their grip on the Senate and many state houses without a national majority.

Because the process of redrawing political maps will not begin until after 2020, House Democrats will have to defend their gains on the same, skewed playing field. Ahead of Tuesdays election, various forecasts posited Democrats would have to beat Republicans by roughly 5.5 , 7, or even 11 points in the general vote just to win a slim majority of seats in the House.

If it requires a generational wave to give Democrats [the House], thats a sign of just how powerful gerrymandering is, not a sign that it can be conquered, said David Daley, the author of Ratf**cked, a chronicle of the GOPs aggressive gerrymandering efforts. Winning back the House does nothing to change that structural unfairness in the future.

Certain factors give Republicans a natural advantage. In the Senate, the disproportionate representation of small states is part of the bodys original design. But that advantage, which benefits white voters , has become more lopsided than the framers of the Constitution likely ever imagined as the countrys population and demographics evolve. Today, 20 senators from urban states represent roughly half the countrys population , while the other, rural half elects the remaining 80.

The House presents similar challenges. Many other democracies ensure that a partys control of the legislature corresponds to its share of the vote. But the United States has a winner-take-all system. Netting 40 percent of the vote in every district would result in a total loss; winning 80 percent of the vote in every district would be no different than winning 51 percent in every district.

Again, the benefit redounds mostly to white, rural voters likely to vote Republican. Because Democratic voters are concentrated in cities, it is inevitable that more of them will find their votes wasted that is, packed into bright-blue districts. And over the past several decades, voters have sorted themselves so that the urban-rural partisan divide is even starker.