For both parties, the last 96 hours before Election Day
is the time to put months, even years-long plans to turn out voters in motion.
In 2016, Republicans are trying to learn from their mistakes. After their lagging 2012 operation failed to elect Mitt Romney, the Republican National Committee began working to step up their game, investing manpower and resources in many key states some three years ago.
"We are 100 miles away from where we were in 2012," said Matt Dailer, the RNC's director in the battleground state of Iowa.
One of the biggest differences between this election cycle and those in the past is that Republican activists and volunteers are working on a new phone app to get out the vote.
"It will show you their party affiliation, how reliable they are as a voter. You just click that voter, do tech survey, boom there you go right there," said Dailer, as he demonstrated the way it works.
It also gives volunteers what's called "dynamic scripting," a tool that prompts different pitches to voters depending on their answers to a set of questions, information instantly sent back to RNC headquarters.
"If we have someone who says the country is going in the wrong direction but they plan on voting for Hillary Clinton, there we go," Dailer said. "Now we know how we can target them."
"We need to talk to low-propensity Republicans to make sure they know when the election is and figure out who they're going to support so we can drive them out," he added.
Now, in the final push, thousands of GOP staffers and volunteers are using that app in battleground states across the country. The RNC, which is leading Trump's ground operation, says it will complete 17 million door knocks by Election Day, up from the 11.5 million it did in 2012.
It's an ambitious plan, but it's been done before -- by the Democrats.
Republican strategists openly admit that they are trying to emulate the Obama ground machine that crushed the GOP for two presidential election cycles.
And this cycle, the Democrats are not slowing down. Armies of Democratic volunteers and activists are spread out over the same key states as Republicans.
Clinton campaign aides say they are expecting to have close to 1 million volunteer shifts in the final 96 hours alone.
In some ways, team Clinton is old school. Unlike the Republicans who do almost everything on an app, the Democrats still distribute call sheets and send volunteers out canvassing with paper and clipboards. All the information is then imputed and tallied at the end of each day.
Still, overall, the Clinton system is very high tech, using social and digital media to build on that vaunted Obama operation. Jessalyn Reid, the Clinton campaign's Virginia state digital director, explained that their technology is all about meeting voters where they are, which in 2016 is online.
"We've got apps and mobile websites and email and all of the stuff that we're going to bring together for a holistic direct voter contact program that really reaches people where they are and enables them to organize their communities and get out the vote both on and off line," she said.
For Team Clinton, getting out the vote is all about decentralizing the process and helping volunteers reach out to people in their own communities.
Democrats also stress the importance of getting their supporters to make a concrete voting plan. Reid demonstrated on her phone how voters can use text messages to nail down every detail, from their polling location to what kind of transportation they will take to what time of day they plan to go. And on Election Day, Reid said those voters will get a reminder straight to their phones telling them to go vote.
With just days until the election, Clinton officials say their volunteers are pretty much done trying to persuade voters to support the Democratic nominee; they are just focused on turnout.
"Right now, and through the final stretch of the campaign, we are talking to Hillary supporters -- so people that we know support Hillary," said Reid.
Republican officials say they are also focusing their phone efforts on turning out supporters, but say their technology makes it possible to continue trying to persuade soft voters door to door, even in the final days of the campaign.
Still, for both sides, on Election Day, all the phone calls, messaging, door knocking, has to translate to one thing: votes.