The Trump campaign is spending nearly half (44%) of its Facebook ad budget to target users who are over 65 years old, as opposed to Democratic candidates who are only spending 27% of their budget on that demographic, according to data given to Axios exclusively from Bully Pulpit Interactive.

Why it matters: In the wake of huge 2018 Democratic gains among young voters, older voters will be even more critical to Trump's strategy in 2020.

Expand chart Adapted from a Bully Pulpit Interactive chart; Chart: Axios Visuals

"We assume Trump is making a huge play to hold an advantage he had in 2016 with older white voters. This follows the public statements from the campaign manager that they plan to target and reach all of their voters online, not just cultivate small-dollar donors."

— Ben Coffey Clark, partner at Bully Pulpit Interactive

Between the lines: Other data points pulled from the Facebook ad archive show that the President is using most of those ads targeted towards older people to talk about immigration.

Trump is using nativist language around immigrants in 54% of his ads, according to BPI. So far Democrats have not responded in kind on the topic of immigration and are focused on fundraising and other policy issues.

"The one thing the Trump campaign has proven time and again is that they follow the results and optimize for outcomes and not the general consensus," says Zac Moffatt, CEO and founder of public affairs firm Targeted Victory, which specializes in corporate and conservative issue campaigns and causes.

How it works: Facebook opened up its ad archive API (application programming interface) for the first time in March in a way that makes it possible to glean insights about a campaign's targeting and messaging strategy. Previously, spend dynamics were available, as was ad creative, but this level of granularity around ad targeting was not.

By the numbers: In total, the Trump campaign is only targeting voters 18-35 with 4.3% of his total ad budget.

Unsurprisingly, Democrats Tusli Gabbard, Bernie Sanders and Beto O'Rourke are doubling down on young people, spending almost four times as much as Trump to reach those voters.

Both Democrats and Trump are targeting middle-aged people, ages 34-65 roughly, at the same percentage of total spend.

Be smart: The Facebook algorithm will usually optimize ads towards younger voters who are easier to reach, which reinforces The Trump campaign's commitment to consolidate its base with older voters.

The big picture: Multiple studies released over the past year suggest that Facebook usage on the core app is tilting much older, as younger users flock to apps like TikTok and Facebook-owned Instagram.