The promise's ultimate end-state — the U.S. actually running on 100% clean/renewable energy by 2050 — cannot yet be judged (deadline ~24 years out; the U.S. has not transitioned off fossil fuels), so it is not FULL. But Merkley's record of leadership is verified and unambiguous: he was the LEAD sponsor and author of the 100 by '50 Act (S.987, 115th Congress) — introduced "for himself, Mr. Sanders, Mr. Markey, and Mr. Booker" — the first congressional bill envisioning a complete transition off fossil fuels to 100% clean and renewable energy by no later than 2050. His office's press release headline confirms the launch verbatim. That vehicle received no vote and died in committee (the normal fate of a minority-party bill), but Merkley sustained the campaign and voted Yea on the Inflation Reduction Act (Senate roll-call vote 325, Aug 7, 2022, H.R. 5376, 50-50 with the VP breaking the tie), which he praised as "the most significant piece of climate legislation ever passed through the U.S. Senate" that "puts us on a path to transition to clean and renewable energy." This is consistent, leading advocacy for the promised transition (CHAMPIONED), not box-checking. Confidence is held near 0.7 because the promised outcome remains aspirational and unmet and the flagship bill never advanced.