Democrats continue to press forward on impeachment, where they have the numbers to win. But will they win that battle, only to find out that they will lose an election they might otherwise win? Not all of the numbers are lining up in their favor, and The New York Times offered them a rude reminder of electoral realities in 2020.

House Democrats have not just cast the die on impeachment, as Nancy Pelosi quoted Julius Caesar's famous line when crossing the Rubicon of Alea iacta est. They have rolled the dice on the 2020 election by setting the expectation that impeachment will succeed, and that it will lead public opinion against both Donald Trump and Republicans in the election. At risk are more than two dozen House seats in districts that originally backed Trump in 2016, as well as an opportunity to beat the GOP in the Senate, where nearly twice as many Republicans as Democrats will defend seats next year.

At least in national polling, Democrats appeared to be winning the gamble in the first month after the whistleblower came forward and House Democrats launched their inquiry in earnest. At that origin point on Sept. 18, FiveThirtyEight's impeachment polling tracker reveals, national sentiment on impeaching President Trump was solidly negative, with 40 percent of Americans in favor and 51 percent opposed. Ten days later, the average polling result had flipped to 47-46 in favor. By Oct. 14, four weeks out from the whistleblower eruption and as testimony leaked out of the House probe, support hit 50.3 percent in the aggregate polling average.

That, however, has turned out to be a high-water mark. Rather than building momentum toward a national consensus for impeachment and removal, support stalled — and then began retreating slightly over the next three weeks. The polling average has returned to nearly an even split at 48.3 in favor and 44.8 against, a gap of only 3.5 points. Polling from both NBC/Survey Monkey and ABC/Washington Post suggests that most of the initial gains Democrats made in support for impeachment came from hardening positions within their own base.

The ABC/Washington Post poll had another warning sign in the crosstabs of their latest survey. Impeachment played much better among urban voters than it did anywhere else, where impeachment support in these Democratic Party core constituencies ran 58-38 in favor. Among suburban voters, however — the same that Democrats won to get their current House majority — that flipped over to 46-51. And rural voters liked the prospect of impeachment even less, essentially mirroring urban voters, 38-58.

At the same time, Trump routinely trails several of the Democratic hopefuls in prospective head-to-head polling nationally, sometimes by double digits. Even if House Democrats might risk erosion in support among suburban voters with their impeachment push, they appeared to be succeeding in their mission of making Trump unelectable.

Of course, if national support mattered, Donald Trump would not be president today. Presidential elections have always been a collection of state elections with the results calculated by the Electoral College rather than a popular vote. National polling numbers ignore the dynamic of 2016, when Hillary Clinton ran up big numbers in deep-blue states but lost enough marginal states to make Trump president.

Mindful of that fact, The New York Times decided to look at Trump's standing in the swing states that will most likely decide the 2020 election: Michigan, Pennsylvania, Wisconsin, Florida, Arizona, and North Carolina. The results presented a shockingly different picture than what had been a constant narrative of defeat. Far from trailing the Democratic front-runners, Trump led Elizabeth Warren in five states with one tie, and Bernie Sanders in four with one tie. Trump trailed Joe Biden in five of six states, but only by two points or less.

Nor was this a fluke. In a separate NYT/Siena College poll of likely Iowa general-election voters, Trump beat all of the Democrats, including Pete Buttigieg. Biden came closest by pulling within a point at 45-44, but Trump led Warren by seven, 47-40. All of this comes as Democrats are criss-crossing Iowa and Trump takes a beating in the national media.

How can this be? Trump is one of the most unpopular presidents — in national polling, sure, but also in state-by-state polling as well. House Democrats have spent all year demanding his impeachment, first over the Robert Mueller special-counsel probe of the 2016 election, then regarding alleged obstruction of justice detailed in Mueller's report, and now over the Ukraine affair. Even if voters aren't necessarily excited about impeachment, any normal politician would have seen their electoral support eroded by now.

The easy response to that is to echo Trump's self-assessment as an extraordinary politician, but the real answer may be less about Trump than it is about these voters. The 2016 election was driven by rejection of the establishment in both political parties; Clinton managed to survive a close primary, but populist voters pushed Trump to the GOP nomination. In the general election, the same voters rejected Clinton's promise of establishment continuity for Trump's disruption of establishment control.

But what about Tuesday's off-year election results, where Democrats made gains in Virginia and especially Kentucky, where Trump campaigned for incumbent governor Matt Bevin? Don't these outcomes suggest Trump is in trouble? Not as much as one would think. Virginia has been trending blue for years before Trump's arrival, and Bevin was personally unpopular in Kentucky — where every other statewide office went to the GOP.

Seen in this light, House Democrats may have set themselves up for a huge backfire. Their demands for impeachment could look very much like a concerted effort by the political establishment to thwart the will of these voters.

Trump ran in 2016 as the only man strong enough to run against the establishment. By pursuing impeachment at all costs, especially with no hope at all of having a Republican Senate removing him, Democrats might inadvertently prove Trump correct — and give him an even stronger populist argument for 2020.

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