Mathematical Economics · University of Pennsylvania

Jonathan
Schwartz

I build election models, data pipelines and the apps I wish existed. Right now I'm a Product/Data Science Fellow at VoteHub, turning election data into articles and tools people use.

236years of election returns in Bellwether
177,021precincts in my national VoteHub data set
3apps across iPhone, iPad, Mac and the web
2028Penn class year

Selected work

05 projects
01/05

Bellwether

Election atlas & forecast · Solo · 2026

An atlas of every certified election return in American history, down to the county and precinct. Anyone can pull up past results, compare places and simulate their own outcome. I built the pipeline, the model and the interface myself.

I collected every result from state and county sources, cleaned it, joined it to Census and polling data, and shipped it as one web app with a full methodology paper behind it.

PythonJavaScriptGeoJSONCensus data
bellwetherelections.com ↗
16.6 billion
votes counted, every certified return since 1788
3,144
counties, plus 167,775+ precincts
10
workspaces, from the county map to redistricting and the Supreme Court
bellwetherelections.comOpen ↗
Explore: every county, 2024 presidential
Simulate: shift turnout and group support
Forecast: 2026 Senate odds of control
Analysis: turnout and margins over time
Voters: North Carolina county scores
02/05

VoteHub

Product/Data Science Fellow · 2026

VoteHub is an election data and media startup. I write its data features, build the data sets behind them and build tools for election night.

First, I built a national data set covering every precinct on the 2020 map. Next, I used it for articles on data centers, AI political ads, Trump's approval and the campus vote. Lastly, I built a race-calling console for election night.

PythonDatawrapperJavaScript
2026 Campaign Tracker ↗
177,021 × 77
precincts by features in that data set
7,190
candidate appearances tracked across 12 Senate and 11 governor races
125
college campuses in 28 states, measured for the campus swing
Oct 28, 2026 · Read on VoteHub ↗
The Data Center Midterm

Voters hate data centers, and campaigns are catching on. But the buildout sits in a handful of states, so only a few races are directly exposed.
Coming soon
Are Campaigns Disclosing Their AI Ads?

31 states require a label on AI-manipulated political ads. Most of the money behind them doesn't carry one.
Coming soon
Where Is Trump Underwater?

Approval modeled in every state and House district from poll crosstabs. Underwater in 157 of the 234 districts he carried.
Coming soon
Did College Campuses Swing Harder?

Campus precincts moved about four points further toward Democrats than their states in 2026.

Charts I made for The Data Center Midterm

Opposition to data centers, every repeated poll
Republicans flipped from backing to opposing
Ten states hold 70% of the buildout
17 of the 20 biggest data center districts voted Trump
03/05

Focs

Focus app for iPhone & Mac · Solo · 2025–now

I wanted one app that blocks distractions, knows my class schedule and shows whether I'm actually getting work done. Nothing did all three, so I built it.

Focs runs Pomodoro and Flowtime sessions, blocks apps through Screen Time and plans each day around your classes. It syncs to a Mac app with end-to-end encryption, and friends can see each other's focus time.

SwiftSwiftUICloudKitScreen Time APIWidgetKit
Recorded in the iPhone simulator
Today: the plan for the day
Focus session tied to a task
Week view around your classes
Fill free time with tasks
04/05

frmat

Feed planner for iPhone & iPad · Solo · 2025–2026

frmat lets you design your social feed before you post. Drag posts around the grid, split one photo into a seamless 3, 6 or 9-post layout and see exactly how your profile will look.

It runs entirely on the device, with no account and nothing uploaded. The App Store listing, privacy label and review notes are ready to submit.

SwiftSwiftUICore ImageStoreKit
Recorded in the iPhone simulator: one panorama, six posts
A 6-post panorama in the grid
Photo Splitter, 9-post preview
Feed Palette pulls the dominant colors
05/05

St. Elmo Late Night

Web app for Delta Phi · 2026

Running a late night at the house used to take a group chat, a spreadsheet and a lot of yelling. Now one app handles all of it.

Brothers sign up for roles, add their guests and see who is up next. The door gets a searchable guest list, the social team gets checklists and a record of no-shows, and the whole thing installs on a phone like a native app.

The demo runs the same code the house uses, with the database swapped for an in-memory one. Every name is invented.

JavaScriptFirebasePWA
Open full screen ↗
The real app on made-up data. Tap around.

About

During high school, I spent a summer at Berkeley Lab analyzing battery storage and grid emissions. I learned R, worked with very large data sets and got one piece of advice I still use: find the intersection between your talents and your passions.

For me, that intersection is data and politics. I study Mathematical Economics at Penn, with minors in Statistics & Data Science and Political Science, and I build tools that make elections easier to understand.

I'm from Berkeley, California, where I rowed on the Oakland Estuary and co-founded a crew to clean it up.

SchoolUniversity of Pennsylvania, Class of 2028
MajorMathematical Economics
MinorsStatistics & Data Science · Political Science
NowProduct/Data Science Fellow, VoteHub
Summer '26PORES Fellow, judicial election advertising data
BeforeBerkeley Lab · COSMOS · Berkeley High School
ToolsPython · R · Swift · JavaScript
Contact

Send me a problem worth solving.

jonats@sas.upenn.edu GitHub ↗