All four cited sources are reachable and each supports the CHAMPIONED outcome for this promise; every quoted string was confirmed against the fetched page. (1) SCOTUSblog confirms McConnell personally FILED amicus briefs in NRSC v. FEC on Jan 6, 2025 and Aug 28, 2025 — verbatim docket text "Brief amicus curiae of Senator Mitch McConnell filed." — arguing that FECA's coordinated-party-spending limits violate the First Amendment. This is an authored/led action within the 119th Congress (begun Jan 3, 2025), squarely advancing the "protecting political speech in elections" priority, and it clears the leadership bar required for CHAMPIONED (proactive Supreme Court advocacy he initiated, not a vote or passive support). (2) The FEC primary source and (3) CBS News confirm the Supreme Court struck those limits down 6-3 on June 30, 2026 on First Amendment grounds — the outcome aligned with what McConnell championed; both headline/sentence quotes match verbatim. (4) NOTUS confirms the "We're not going to do that" Bloomberg quote in the exact context of Trump's push to abolish the legislative filibuster during the Nov 2025 shutdown, documenting active public defense of the institution. Confidence held at 0.73 because the promise is a broad statement of "priorities to pursue" rather than a specific deliverable, and the institution/filibuster prong is shared leadership (Majority Leader Thune is the driving figure). But because at least the political-speech prong rests on authored amicus briefs — genuine leadership — CHAMPIONED is upheld rather than downgraded to FULL/PARTIAL.