Sen. Byrd has passed away:

Robert C. Byrd, who used his record tenure as a United States senator to fight for the primacy of the legislative branch of government and to build a modern West Virginia with vast amounts of federal money, died at about 3 a.m. Monday, his office said. He was 92. He had been in failing health for several years.

Mr. Byrd’s death comes as Senate Democrats are working to pass the final version of the financial overhaul bill and win other procedural battles in the week before the Independence Day recess. In the polarized atmosphere of Washington, President Obama’s agenda seemed to hinge on Mr. Byrd’s health. Earlier this year, in the final days of the health care debate, the ailing senator was pushed onto the Senate floor in his plaid wheelchair so he could cast his votes.

Mr. Byrd served 51 years in the Senate, longer than anyone in American history, and with his six years in the House, he was the longest-serving member of Congress. He held a number of Senate offices, including majority and minority leader and president pro tem.