Like Napoleon, Hillary Clinton’s long career ended in Waterloo. Only in her case, it was Waterloo, Iowa. She trailed Barack Obama’s 2012 totals by 9 percent in Waterloo’s Black Hawk County, helping President Trump win the White House, which he did by capturing votes in areas that Democrats overlooked.

In fact, Iowa, our almost-neighbor, had one of America’s largest swings from Democrat Obama in 2012 to Republican Trump in 2016. How — and where — did it happen, and what does that mean for Kansas this year? For one thing, it means that on election night, Lyon County is one to watch — an electoral battleground, the Iowa of Kansas.

In Iowa, the 2016 race was not won or lost in the state’s more-populated, Democratic strongholds like Polk, Johnson and Story counties (Des Moines, Iowa City and Ames, respectively). These areas did not shift much between 2012 and 2016, going almost as strongly for Clinton as they had for Obama. Instead, Clinton got shellacked in Iowa’s rural counties. In many, support for Democrats dropped 15 percent or more between 2012 and 2016. Most of those rural areas had voted for Romney in 2012, but the huge drop in Democratic percentage, in many cases going from the mid-40s to less than 30 percent in only four years, was pivotal. These are the places where many Obama-to-Trump voters live, and those voters are the ones that decided the election. Similar patterns are evident in larger states like Ohio.

What about Kansas? This state may not be competitive in presidential races, but we did see one of the closest races in recent state history when Paul Davis challenged Sam Brownback for the governorship in 2014. The comparison is cruder, because turnout is lower in midterms, but it is still telling. In fact, boosting midterm Democratic turnout in these areas is a crucial piece of the puzzle, and it can be tough when people get discouraged, because they know they are a minority among their neighbors.

Identifying the counties with the biggest Davis-to-Trump shifts shows us where to look. It is important not to overlook counties that Davis did not in fact win but where he performed much better than did Clinton. This means places like Pawnee County (Larned) — 44 percent for Davis in 2014 but only 21 percent for Clinton in 2016. Butler County (El Dorado) is similar — 38 percent for Davis but only 21 percent for Clinton. In Lyon County (Emporia), Davis won outright with 62 percent, while Clinton could only muster 37 percent — one of the biggest shifts in the state. Even very Republican western Kansas counties have persuadable voters. Davis’ 28 percent in tiny Lane County (population 1,750) may seem low but clearly surpasses Clinton’s abysmal 12 percent.

If 2016 was a realigning election — if these new changes are long term — then Democrats are in a world of hurt here. But such large swings are likely to be temporary, influenced in part by Clinton’s personal unpopularity. Laura Kelly, the Democratic nominee for governor, and the others do not need to win most of these counties outright, but Democrats should not ignore the voters here. Their few urban and college-town Kansas strongholds are not enough. Johnson County has become a battleground to be sure, hardly safe Democratic territory. Wichita and Topeka remain highly competitive. Democrats certainly need to win in the cities and suburbs, but they also need to remember the voters in counties they usually do not win. If they turn out their base, cut their losses outside the cities and bring home the Davis/Trump voters, the Democrats may just capture the governor’s mansion this year.

— Michael A. Smith is a professor of political science at Emporia State University.