 He's worried about what he called a consolidation of power. A number of Tillis' proposals would give the next GOP leader more power over issues like committee assignments. He argued that changes could help conference priorities and messaging. Lee disagreed. The back and forth is the latest example of growing tensions within the Republican conference over not only who will lead them, but what powers that person should have. Senate Minority Leader Mitch McConnell is planning to step away from his post late this year. Conservatives demand changes from whomever succeeds McConnell.