"federal office" refers to the presidency, vice-presidency, the Senate, and the House of Representatives.

The candidate representing the "third party" cannot be an independent (nor a Democrat, or a Republican).

To "win" a federal office means the office must be obtained by the third party in an election, so an elected Democrat, Republican, or independent joining a third party in an office that they won beforehand as one of the above would not count.

This question will include results from the 2028 elections and can resolve to presumptive winners as of December 2028 (which is to say, this question does not need to wait until a third party's candidates are formally in-office and can resolve to the confirmation of their election).