Des Moines, Iowa (CNN) Sen. Bernie Sanders is likely years away from deciding whether he'll run for president again in 2020, when he'd be 79 years old on Election Day.

But by keeping his base energized through visits -- including a boisterous event here last weekend -- and with his allies increasingly stepping into local races and gaining power inside the Democratic organizations they felt locked out of in 2016, Sanders' message is clear: The 2020 Iowa caucuses will take shape around him.

Sanders came inches from besting Hillary Clinton in Iowa in 2016. His political organization has become more sophisticated since then, both nationally with Our Revolution, the progressive group spawned by his campaign, and in the states, where supporters are organizing to provide him a clear path to the nomination -- if he wants it.

Whether he runs again or not, Sanders' backers and Iowa Democratic strategists say the Vermont senator's strength in the Hawkeye State will force other candidates to either embrace his influential message or risk running up against it.

"If you're talking 2020, regardless of what the name of the person is, as this party moves forward, the things that Bernie Sanders talks about are starting to coalesce as the things that you're going to need to address in order to be successful in the party," said Pete D'Alessandro, who was Sanders' Iowa campaign director in 2016, continues as his main conduit in the state now and will soon likely become a Democratic candidate himself in a competitive race for Republican Rep. David Young's US House seat.

Sanders' followers step into local races

When Sanders began selling his "political revolution" in his first trip to Iowa in May 2015, he had a bare-bones campaign infrastructure and no significant support from local elected officials.

Twenty-six months later, Sanders-backers have landed positions in Iowa's county and state Democratic parties and are candidates in its governor's race and, in D'Alessandro's case, at least one congressional contest.

When Sanders arrived last Saturday for his first Iowa visit of 2017, D'Alessandro drove him to the populist Iowa Citizens for Community Improvement's convention, where 750 activists had gathered for detailed sessions by 9 a.m. -- hours before Sanders would arrive.

"During his campaign I saw how things worked and I realized that if I wanted to be more impactful than just showing up at rallies and organizing or taking an arrest, if I wanted to change the political landscape, that I would have to commit to being involved in the party," said Jessica Fears, a 30-year-old waitress who has landed posts with the Story County and state Democratic parties and is a member of the Iowa Citizens for Community Improvement.

D'Alessandro said the evolution has been stark.

"We had nobody -- six elected officials in the whole state," he said. "We did have a scattering of some county chairs that were for us. But we had nobody on the state central committee. The highest ranking elected official in Iowa who endorsed Bernie Sanders was county supervisor. We had nobody above that level, we had nobody in the statehouse, we had no statewide electeds. We had no one."

"So when you go from zero to almost half of the state central committee of people who said they were Sanders folks, that's a big, big jump," the Iowa veteran added. "These things usually take longer."

Democrats in the state and nationally who are more pessimistic about a Sanders 2020 campaign say they see him as the front-runner by virtue of his organizational head start and his influence on the party's policy positions on health care, college affordability and income inequality -- but they don't see him as the favorite in a nominating contest still years away.

Sanders' age and the questions about his wife Jane Sanders' actions in her role at the now-defunct Burlington College are potential liabilities. Democratic operatives also say Sanders would face heavier and wider-ranging attacks on his politics and character in a wide-open primary than he did against Clinton, whose team was confident for much of their battle that her delegate lead would hold.

And while they concede that Sanders' allies have grown in numbers in the county and state parties, they're also quick to note the next state chair and the party's 2018 gubernatorial nominee aren't likely to come from his political orbit.

The core of Sanders' permanent Iowa team includes D'Alessandro; Evan Burger, who was Sanders' deputy state director and is now a senior organizer for the group that hosted him over the weekend; and Robert Becker, a 2016 Sanders campaign veteran who recently returned to Iowa to consult for D'Alessandro's expected congressional bid and in the governor's race.

Despite their growing influence, Iowa Democrats in Sanders' camp aren't talking about 2020 yet -- at least not out in the open.

A competitive primary to take on Republican Gov. Kim Reynolds next year, combined with turmoil at the state Democratic Party -- where the chair, Derek Eadon, resigned in late June, citing health reasons -- are "sucking all the air out of any discussion of 2020," one Democratic operative there said.

And in Iowa, like elsewhere, Democratic voters are preoccupied with fighting President Donald Trump -- with most of activists' energy in recent months being poured into the health care battle.

Too early for 2020

Nationally, ambitious Democrats know not to focus too heavily on 2020 -- so they've been cautious about treading too heavily onto early-state terrain.

Sanders will make his second visit for a book talk in Iowa City on August 31. Minnesota Sen. Amy Klobuchar, who Democratic operatives have said has been more frank than many about her presidential aspirations, will be in Ames the same day for her second visit to Iowa in 2017.

Other Democratic prospects like Ohio Rep. Tim Ryan, former Missouri Secretary of State Jason Kander and former Maryland Gov. Martin O'Malley have all visited the state.

Meanwhile, other potential candidates are taking policy stances that align them more closely with Sanders. New York Sen. Kirsten Gillibrand, for example, supports "Medicare-for-all" single-payer health insurance -- and Democrats increasingly believe such a program will be a central focus of the 2020 primary.

Iowa Democrats say they see Sanders as intent to steer the party's 2020 dialogue toward his core issues -- and keeping up a front-runner's appearances, whether he runs or not, allows him to do that.

Sanders has said it's too early to answer questions about whether he will run for president again in 2020.

"I am not taking it off the table. I just have not made any decisions. And I think it's much too early," Sanders told SiriusXM's Mark Thompson last week, while insisting Democrats face more urgent fights against Trump. "It just too early to be talking about an election three and a half years from now."

Still, Sanders has, through phone calls, trips and in his own small ways, continued to cultivate a relationship with progressives in the state.

One of those small ways: Instead of bolting from the stage, as he usually does after speeches, Sanders lingered Saturday, shaking hands and taking pictures.

Fears pointed out that "if you notice in a lot of his videos, there are a lot of people from Iowa. There are scenes from Iowa. So I think he does have a connection because he has been here so many times."

Chris Laursen, the president of the United Auto Workers Local 74 and a Sanders delegate from Iowa at the 2016 Democratic National Convention, lost an election to become the state party's labor caucus chair this year and said he'll run again in 2018.

"We have almost enough Berners to hold the majority. It's real close," he said.

"Instead of being an outsider coming in, we've got a seat at the table now," Laursen said. "And we're gonna take over the table."