WASHINGTON — America and the world mourned Sen. Edward M. Kennedy yesterday, recalling the veteran Massachusetts senator as a legislative lion who had a knack for accomplishing the toughest Senate tasks.

Kennedy's Senate seat — back row, second seat from the left, the same one his brother, John, had occupied as a senator — was shrouded in black, and Washington put aside its partisan ways and reflected.

Barack Obama, whose presidential bid got an important endorsement from Kennedy early last year, issued a proclamation declaring Kennedy "not only one of the greatest senators of our time, but one of the most accomplished Americans ever to serve our democracy."

The president, vacationing in Martha's Vineyard, was awakened after 2 a.m. yesterday and told that Kennedy, 77, died Tuesday night after a 15-month battle with brain cancer. Obama spoke soon after with the senator's widow, Victoria, and ordered flags flown at half-staff at the White House and all federal buildings until sunset Sunday.

Kennedy's body will lie at the John F. Kennedy Presidential Library & Museum at Columbia Point in Dorchester, Mass., starting today. A memorial service will begin at 2 p.m. tomorrow (Hawai'i time) at the library; it's not open to the public.

On Saturday, the senator's funeral Mass will be held at Our Lady of Perpetual Help Basilica in Boston, where Kennedy prayed daily when his daughter, Kara Kennedy Allen, was diagnosed with cancer. She survives him, along with his wife, Vicki; two sons, Edward Jr. and Rep. Patrick J. Kennedy, D-R.I.; two stepchildren, Caroline and Curran Raclin; and a sister, Jean Kennedy Smith.

A White House official said Obama would deliver a eulogy at the funeral. The official spoke on condition of anonymity because the Kennedy family had not yet made an announcement.

Saturday at noon (Hawai'i time), Kennedy will be buried at Arlington National Cemetery, where his brothers John and Robert, as well as Jacqueline Kennedy, were laid to rest. The burial also will not be open to the public.

PRAISE AND SORROW

Kennedy collaborated with a Republican president, George W. Bush, on education reform; with a Republican presidential candidate, Sen. John McCain of Arizona, on immigration reform; and with an arch-conservative senator, Strom Thurmond of South Carolina, on major crime legislation. Only Thurmond, who died in 2003 at age 100, and Sen. Robert Byrd, D-W.Va., served longer than Kennedy in the Senate.

Praise and sorrow poured in from all political quarters yesterday.

"He was grounded by a fundamental sense of right and wrong, and our country was better for it," said House Education and Labor Committee Chairman George Miller, D-Calif.

McCain, Obama's 2008 Republican rival, recalled that "in the quarter-century that I've been here, there's not been anyone quite like him."

Some of the recollections were intensely personal.

"I lost my best friend in the Senate," said Sen. Christopher Dodd, D-Conn. He recalled his own recent cancer surgery, the death of his sister and other personal crises through the years.

"There are examples that go back 30 years. The moments you needed to hear from someone when feelings were hard to express, Ted Kennedy has been there," he said.

Vice President Joseph Biden choked up as he recalled Kennedy. As a U.S. senator from Delaware until earlier this year, Biden worked alongside Kennedy for 36 years through fights on health care, legal affairs and national security.

"He was never defeatist. He never was petty," Biden said, adding that "in the process of his doing, he made everybody he worked with bigger; both his adversaries as well as his allies."

Kennedy was a dominant figure in the Senate almost from the day he arrived in November 1962, elected to fill the seat his brother John had left two years earlier to become president.

The then 30-year-old Kennedy, the youngest of four brothers, was no typical rookie senator. "He had a set of advantages that almost never appear for a senator," said Steven Schier, professor of political science at Carleton College in Northfield, Minn.

His first floor speech was to urge colleagues to pass the 1964 Civil Rights Act, which his brother, President Ken- nedy, had championed before he was assassinated the previous year, and he became a leading voice for the rights of the poor, the labor movement and public education.

During nearly 47 years in the Senate, he played a key role in shaping national policy on a wide range of issues but especially health, education, civil rights and labor issues. More than 550 of his bills were signed into law, according to his office.

TIES TO IRELAND

Nowhere outside of America has the Kennedy legacy been more deeply felt than in Ireland.

"He lived to see two great chasms bridged, between Catholic and Protestant in Northern Ireland and between black and white in his own United States," former Irish Prime Minister Bertie Ahern said. "These achievements, which were the dreams imagined by his brothers in his youth, were the legacy of a long life and of a good and great man."

U.N. Secretary-General Ban Ki-moon praised Kennedy for "keeping and upholding the ideals and goals of the United Nations" and said his work "will be long remembered in the minds and in the hearts of many people, particularly vulnerable people, and those people whose human rights have been abused."

"He had been the voice of the voiceless and the defender of many defenseless people," Ban said.

DECLINING HEALTH

There were signs recently that Kennedy's health was deteriorating.

His Senate seat was empty on Aug. 6 when colleagues confirmed Sonia Sotomayor to the U.S. Supreme Court, and he didn't attend the funeral service for his sister, Eunice Kennedy Shriver, who died on Aug. 11. The next day, he was a no-show at the White House to receive the Medal of Freedom.

Still, Dodd said Kennedy remained "very much a part" of the health care debate. "He always knew what was going on," Dodd said.

Yesterday, Dodd recalled Kennedy's lessons. Bring your views to the debate, he would say, but "remind people you were elected to get a job done." And that while disagreement is fine, don't be disagreeable.

Most of all, don't give up hope something can get done. "The mistake people make is there's some set formula that applies in every fact situation," Dodd recalled Kennedy as saying, but every legislative fight is different, and people should not get discouraged because a debate is not going down its expected path.

And when the committee finally ironed out details of its proposed legislation, Dodd said, Kennedy wanted details — "like he'd never been sick."

The Associated Press and Washington Post contributed to this report.