It's a political strategy that's called "the full Grassley," named after Iowa Sen. Chuck Grassley, who makes it a point to get some real personal, quality time with every single community each year. Cruz has at least 14 counties to go before Monday, according to The Des Moines Register's extremely handy Candidate Tracker
But Cruz's travel schedule has set up an awkward last-minute sprint to the finish.
While other Republican contenders are heading to cities to rally up the big crowds, the Texas senator is trying to cram in stops to the less populated Iowa counties he hasn't visited already.
It's hugely different from the unconventional but so far winning strategy of billionaire businessman Donald Trump, who has focused on Des Moines and other big towns. Traditionally, presidential candidates try to visit lots of tiny communities in Iowa -- the aim of Cruz's trek. But Trump will typically fly in with his private jet, hold an event that draws crowds of thousands from nearby towns, then fly out.
Trump is leading Cruz in Iowa by 11 percentage points -- 37% to 26%, according to a recent CNN/ORC poll
, though just weeks ago polls showed the two fighting for the lead.
"Typically that doesn't work. Caucus-goers expect to see the candidate, early, often and throughout the entire process," said Christopher Larimer, a political science professor at the University of Northern Iowa, said of Trump.
He said Trump's "impersonal campaign" shouldn't be working -- but it does.
Historically, the "full Grassley" tour helps gain serious support. Former Pennsylvania Sen. Rick Santorum did it in 2012 and won. But then again, so did ex-Congresswoman Michelle Bachmann, and she lost. Mitt Romney -- who narrowly lost Iowa to Santorum in 2012 -- didn't even bother to tour the whole state, but capitalized by working just a few, big counties.
This time around, Santorum did it early -- maybe too early -- for all his handshaking and picnics, he's barely scraping by at 1% in Iowa. He's now working on a second full tour of the state.
Former Gov. Mike Huckabee also pulled off a 'full Grassley" this time, too -- with 150 stops in Iowa in January alone. But he's trailing in sixth place.
"It's not like something magical happens once you complete the 99-county tour. What matters is what you do while accomplishing it," said Craig Robinson, editor-in-chief of The Iowa Republican
In Iowa, the rule is: Spend the extra time with us, and we'll spend the extra time on you. That's meaningful, because voters don't just stop by the polls on primary election night. Instead, they hold lengthy meetings called "caucuses" in which they discuss their preferred candidates.
And that's why Cruz is sticking to his plan, pundits say.
On average, only 20% of Iowa voters actually end up participating in the state's caucus, according to Larimer. That means Cruz doesn't have to focus on winning over the most people -- just those who are most passionate about voting.
And they may just live in the farmlands, not the cities.
"We have to see results Tuesday to see if Trump has rewritten the playbook," Larimer said. "If Cruz wins, the 'Full Grassley' still applies."