Who will win the next Senate Democratic Leader election?

If Chuck Schumer wins the next Senate Democratic Leader election, then the market resolves to Yes.

The market resolves based on the official certification or declaration by the relevant electoral authority. For parliamentary elections, the party or coalition with the most seats wins. For referendums, "Yes" and "No" are the options. For presidential or direct elections, the candidate who wins according to the electoral system (electoral college, popular vote, or runoff as applicable) is the winner. Markets resolve based on official results, not exit polls or projections. If elections are postponed beyond the expiration date, markets resolve to No. Contested results are resolved based on the final certified outcome by the appropriate electoral authority or highest court with jurisdiction.

Outcome verified from or equivalent electoral authority of the relevant jurisdiction; the formal proclamation by the head of state or government when constitutionally required; for religious elections, in hierarchical order: Primary Sources: the official electoral commission and constitutional court.