Shreveport Times: Two Louisiana Democrats — U.S. Sen. Mary Landrieu and U.S. Charlie Melancon — could play key roles in negotiating and crafting their party’s climate control bill, which would have a major impact on the state’s oil and gas industry. Melancon and Landrieu are moderates. Landrieu serves on the Senate Energy and Natural Resources Committee, Melancon on the House Energy and Commerce Committee. Attention is focused on the House of Representatives, where Democrats hope to vote on a …