Summer in Iowa is defined by its constancy. Every year the corn starts shooting up in the fields, Fourth of July parades wend their way down Main Street and fireflies flicker in the warm twilight. And, of course, there are always presidential candidates.

Although the 2016 Iowa caucuses are at least two and a half years away, presidential hopefuls are already descending upon the Hawkeye State with a sense of urgency that even the most rabid political junkie might find a touch unseemly. Starting with Sen. Marco Rubio’s visit to Iowa mere weeks after the 2012 election, the state has been crisscrossed by potential 2016 candidates who all have two characteristics in common; they are all deeply ambitious politicians and they are all Republicans.

No potential Democratic candidates have appeared in Iowa for the 2016 cycle. This marks a major change from the last competitive Iowa Democratic caucuses. By this time in 2005, John Edwards had already visited the state twice, Mark Warner had spent two days in the state, and several others had already planned visits. When the Iowa Democratic Party held a major fundraiser in June, the keynote speaker was Tom Harkin, the state’s longtime Democratic senator.

One Iowa political insider has heard rumblings that Maryland Gov. Martin O’Malley might be considering making a visit to the Hawkeye State soon, but this was shot down by Lis Smith, an O’Malley adviser, who said that the Maryland governor had “no plans” to visit the state in the near future.

According to Jerry Crawford, a trial attorney and major Democratic powerbroker in the state, there’s one reason and one reason why no Democrats are visiting the state: Hillary Clinton. As Crawford, who was a Clinton backer in 2008, told The Daily Beast, Democrats have “an extraordinarily strong presumptive frontrunner and most people are of the view that they should not actively pursue [the nomination], until Hillary has made up her mind.”

This doesn’t mean that there isn’t any activity. Tyler Olson, a state legislator and former Democratic Party chair, says that while some activists are having very preliminary conversations about organizing, there’s not much else going on. It’s generally known who is a devout supporter of Hillary Clinton or Joe Biden, but “there’s not a lot of effort to grow networks” of candidate supporters beyond those who are already diehards.

In contrast, every Republican Party rubber-chicken dinner seems to be hosted by a presidential contender; the Republican Party of Iowa held one hosted by Rand Paul in May followed by another two weeks later in Polk County (the state’s largest county and which includes Des Moines) hosted by Wisconsin Gov. Scott Walker. In fact, there’s even one party dinner scheduled for August in Rock Rapids, Iowa (population, 2,659), that will be hosted by Rick Santorum.

Republican hopefuls aren’t just attending party events but also paying court to key activists in the state. Both Ted Cruz and Rick Santorum have already agreed to speak (along with Donald Trump) at an August 10 event sponsored by the Family Leader, a social-conservative activist group in the state. This will mark Cruz’s second visit to court Iowa social conservatives; the freshman senator, along with Rand Paul, is appearing at a summit of conservative pastors in Des Moines on July 19.

The presidential candidates aren’t just visiting, but they’re also building their political organizations as well. According to Republican activist and blogger Craig Robinson, there are already natural constituency groups among Iowa Republicans dating back to past caucuses with “the Santorum faction” and “the liberty movement” of supporters of both Rand and Ron Paul. Phone calls are being made and there is already significant organizing going on. He’s even anticipating that candidates may have staff on the ground in Iowa by next year.

This Democratic absence from Iowa will not last forever. As the midterm elections draw closer, presidential hopefuls from both parties will actively show up in the state, ostensibly only to help down-ballot candidates of course. But, as Republican contenders crisscross the state, it’s still surprising that no one has showed up. As Jerry Crawford said, “In Iowa, there’s no such thing as the word ‘early’ when it comes to the caucus.”