API, one state
per state
Every endorsement in one state, with the elections, contests, candidates, measures and endorsers behind it, through December 31, 2027.
Buy API, one stateEndorsement data for researchers
Who endorsed whom, in races and ballot measures across the country: parties, unions, newspapers, advocacy groups and officials, each tied to the choice on the printed ballot and to the page it came from. Structured so AI assistants and agents read it right. Query it with the BallotData API, or just ask your AI through our MCP server.
Every record has the election, contest, district, ballot choice, endorser category, source link and date published, in the same fields in every state.
New The only MCP server for U.S. endorsement data
Our MCP server is the best way to bring BallotData into Claude, ChatGPT and other AI assistants. Ask in plain language who endorsed a candidate, what a union or newspaper endorsed, or what changed this week, and your assistant looks it up through your own API account, in the states you bought.
Included with every API purchase, at no extra cost. How to connect
Server address
https://mcp.ballotdata.ai/mcpAdd it as a custom connector (MCP) in Claude, ChatGPT or your AI tool, then sign in with your BallotData API email and password.
2026 election numbers
Who it’s for
Study how parties, unions, newspapers and advocacy groups line up across the country, with the same fields in every state and a source for every record.
Compare coalitions on ballot measures from state to state, and see which endorsers back which side of the same question.
Pull every endorsement in the states you cover into a notebook or a spreadsheet, without copying slates by hand.
Track who backs your opponents, and every group’s slate across your state, from one query.
Why BallotData
An MCP server for Claude, ChatGPT and other assistants, an OpenAPI spec that describes every parameter, and Python and JavaScript libraries. Endorsers come with categories, so you and your AI can filter to labor, newspapers, parties and more.
Endorsements from across the country in one dataset. We gather them from published slates, voter guides and endorsement pages in every state we cover.
Each endorsement points to the exact choice voters see: a candidate, a ranked slate, or Yes or No on a measure, with the contest’s voting rules.
Every endorsement keeps the link it came from and the date it was published, so you can cite it and check it.
Pricing
One state or every state we cover. One payment licenses the data through December 31, 2027, including every endorsement we add until then and the MCP server for AI assistants.
per state
Every endorsement in one state, with the elections, contests, candidates, measures and endorsers behind it, through December 31, 2027.
Buy API, one stateevery state we cover
The nationwide endorsement dataset: every state we cover, with the elections, contests, candidates, measures and endorsers behind it, through December 31, 2027.
Buy API, nationalNew endorsements as we find them, by email, as CSV or JSON files, over a live stream or as a postback to your server, usually within the hour for endorsers we already follow. It’s coming back for the 2028 elections and isn’t sold until then. What’s in it
Every field is in the API reference, with examples. Or tell us about your research and we’ll help you pick the right plan.
If your organization publishes a slate or voter guide, send us the link and we’ll add it. It’s free, and your picks reach voters through endorsedby.org.