The deal to avert a change in Senate cloture rules is more than just a temporary outbreak of sanity in this highly charged partisan accelerator chamber. It amounts to a transfer of leadership from the polarized, party leaders to the narrow but critical center of the institution. Majority Leader Bill Frist (R-Tenn.) still has the corner office, and Minority Leader Harry Reid (D-Nev.) still has the key to the executive washroom, but it is the 14 senators who crafted this deal who now are the people to see in the Senate. Few realized that when the Republicans garnered 55 seats...