In the U.S. Senate, where seniority is currency, U.S. Sen. Daniel Inouye is now first.
Inouye was sworn in yesterday as Senate president pro tempore, the presiding officer in the absence of the vice president. The Hawaii Democrat was chosen after he became the chamber’s senior member with the death of his friend U.S. Sen. Robert Byrd, D-W.Va.

Inouye, 85, who has served in the Senate since 1963, is now third in line to the presidency after the vice president and the House speaker.

Inouye will have official signing authority over bills and other Senate documents and will choose senators to preside over the chamber during floor sessions. The ceremonial position comes with a security detail and a salary increase.

The senator will earn $193,400 a year, the same as the Senate majority and minority leaders, compared with $174,000 for a rank-and-file member.

His elevation to Senate president pro tem, and his chairmanship of the Senate Appropriations Committee, give Inouye unrivaled stature in a chamber that prizes seniority and honors powerful committee chairmen.

Byrd, 92, held both distinctions before illness forced him to step aside as Appropriations chairman last year. Inouye said he could not celebrate under the circumstances.

"I’m not in the mood for it," the senator said by telephone from Washington, D.C. "I knew that he was ill, but you always find it difficult to say goodbye. I owe much to him. I would have hoped that my new responsibility would be given to me under different circumstances. This was the result of his death. Those are not the circumstances I would prefer."

Inouye said he was briefed on his security detail yesterday and expected to meet with White House security and communications officials today. He described it as "a new life for me."

"It’s a challenge but I welcome challenges," he said. "Without challenges life can be very dull. I don’t relish dull lives."

Inouye became the second-longest-serving senator in history earlier this month, surpassing the late U.S. Sen. Strom Thurmond, R-S.C. Byrd, who entered the Senate in 1959, was in his ninth six-year term.

Inouye is running for his ninth term this year and would eclipse Byrd in about four years if he remains in the Senate.

In a statement, Inouye, known for his ability to secure federal money for Hawaii, praised Byrd for his advocacy for West Virginia. Some critics have described Byrd as the "King of Pork" for the volume of federal dollars he steered to his home state. But Byrd relished the moniker, just as Inouye has when it has been used against him for obtaining federal earmarks for the islands.

"He was a senator’s senator," Inouye said. "His many accomplishments were historic, and he fought tirelessly to improve the lives of working families in West Virginia. We shared the belief that we must provide for the people who trust us to represent their communities in Washington."

U.S. Sen. Daniel Akaka honored Byrd in a tribute as "my mentor, supporter and good friend."

"Sen. Byrd was the dean of the Senate, our foremost constitutional scholar," Akaka said. "No one in the history of our country served longer in Congress. For more than half a century, Robert Byrd kept the Senate in line. He always kept a copy of the Constitution in his jacket pocket – close to his heart. He was meticulous, a master of the rules of this historic institution. Through hard work and dedication, Sen. Byrd became an institution himself."

In a statement, U.S. Rep. Mazie Hirono said Byrd "displayed an ability to grow and to change based on knowledge and experience acquired through his service – qualities I truly admire."

U.S. Rep. Charles Djou sent his condolences to the Byrd family for what he described as the senator’s "decades of exemplary public service." He also said in a statement that he looked forward to working with Inouye in his new role.

According to the Senate historian’s office, the Senate president pro tempore ("for the time being" in Latin) is a constitutionally created position that used to be filled by senators based on popularity, competence and reliability.

Since around World War II, the position has traditionally gone to the senior member of the party that holds the Senate majority. The Senate president pro tempore presides over the Senate in the absence of the vice president, who is the Senate’s presiding officer under the Constitution and has a tie-breaking role in the chamber.

The Senate president pro tempore is third in the presidential line of succession, meaning Inouye would become president if President Obama, Vice President Joe Biden and House Speaker Nancy Pelosi were unable to serve.

"It’s a position of great respect and of great honor in the Senate," said Betty Koed, the Senate’s associate historian.

Walter Dods, a financier and Inouye confidant, described the senator’s new role as special for Hawaii and another honor in a nearly 48-year Senate career. But he said it also comes with the burden of greater responsibility.

"The first thing that came to my mind was, really, saying an extra prayer for Dan," he said.

CORRECTION: Sen. Robert Byrd served 51 years in the U.S. Senate. A subheadline in a previous version of this story said he had been in office 34 years.