Stop me if you’ve heard this before: Hillary Clinton should have gone to Wisconsin. This now-familiar trope of 2016 postmortem punditry made an impression on the candidate herself: In her book What Happened, Clinton writes, “If there's one place where we were caught by surprise, it was Wisconsin … if our data (or anyone else's) had shown we were in danger, of course we would have invested even more.”

Would a few trips to America’s Dairyland have made a difference? Research shows little evidence that appearances can change election outcomes, and to the extent that appearances matter, it is because they lead to volunteer sign-ups and contributions. The reason to visit Wisconsin, therefore, would be to excite the base and motivate those supporters to volunteer for the campaign.

Getting out the vote relies on more than excitement, however. Translating enthusiasm into action may require establishing a “ground game.” Campaigns open field offices that serve as points of coordination for volunteer activities, where the data possessed by national campaigns is translated into walk packets and call lists for local volunteers, who in turn talk to voters and collect more data at the doors and on the phones. Offices can increase candidate vote share and turnout in an area, but perhaps more importantly, they indicate to volunteers and local activists that the national campaign cares about their area.

The Clinton campaign’s data-driven belief that Wisconsin did not need more resources might have been incomplete if it relied on an insufficient field operation. In conversations with voters, volunteers can assess their support and relay that data back to headquarters. Better field operations lead to better data, which improves targeting and persuasion, starting the cycle anew.

The decline in field investment from 2012 to 2016 was steepest in Ohio, where Clinton’s 81 offices paled in comparison to Obama’s 132

Clinton’s efforts in the field simply did not measure up to Barack Obama’s: Democrats were concerned throughout the campaign that Clinton was not assembling the “army of volunteers” necessary to get out the vote, and that worry may have been well founded. Clinton had 537 offices around the country, much fewer than Obama in 2008 (947 offices) or 2012 (789) across the map and particularly in battleground states.

Clinton’s campaign went to Wisconsin, even if she did not, but only opened 40 offices — just over half of Obama’s total of 69 in 2012. In Milwaukee County, the largest source of Democratic votes in the state, Clinton opened only four offices compared to Obama’s 10. Dane County, home to Madison, received only three offices, compared to seven from Obama. Outside the large cities, Clinton failed to open offices in 10 counties (with a total population exceeding Madison) where Obama had an office in 2012, including counties where she received more than 40 percent of the vote, such as Richland, Portage, and Douglas counties.

Democratic turnout declined by approximately 44,000 votes in Milwaukee County alone from 2012 to 2016, from more than 332,400 votes to nearly 289,000, a margin greater than Clinton’s loss in the state. Clinton could have withstood her losses in rural communities with only 23,000 more votes out of Milwaukee, before even addressing the 10 ignored counties above. Given the stakes of Milwaukee turnout, failing to match Obama’s ground game there seems like a mistake in hindsight.

Another Midwestern state starkly illustrates the differences in Obama and Clinton’s approaches. The decline in field investment from 2012 to 2016 was steepest in Ohio, where Clinton’s 81 offices paled in comparison to Obama’s 132. In the major cities, Clinton pulled back substantially, opening nine offices in Cuyahoga County (Cleveland) and seven in Franklin County (Columbus), compared to 13 and 12, respectively, for Obama in 2012.

Meanwhile, in rural Western Ohio, counties such as Defiance, Auglaize, and Miami did not receive a Clinton office in 2016 after having Obama offices in both 2008 and 2012. (Clinton underperformed Obama and received below 30 percent of the vote in each of those counties.)

Clinton did not open fewer offices because of a strategic decision to prioritize Democratic areas over rural, Republican ones: She invested substantially less in both. Obama set a standard that Clinton failed to match, and activists and voters in areas that did not see a Clinton field office may have felt that absence.

I cannot and do not claim that having more field offices would have won the election for Clinton. However, in an era of campaigns where money is little object, fighting for every voter on the ground should be fundamental to Democrats’ strategy. The data may not have indicated that something was wrong, but with fewer volunteers in the field, that data was incomplete. Data and field are not competing resource centers; they should work together seamlessly, each benefiting from the insights of the other. In 2020 (if not sooner), Democrats would be wise to at least replicate Obama’s efforts from 2012 and leave it all on the field.

Joshua Darr is an assistant professor of political communication in the Manship School of Mass Communication and the department of political science at Louisiana State University, focusing on campaign strategy and the media. Find him on Twitter @joshuadarr.