Former President Bill Clinton, center, laughs with Mr. Bumpers as Clinton is introduced by Arkansas Gov. Mike Beebe during a 2008 campaign rally. (Danny Johnston/AP)

Dale Bumpers, an Arkansas Democrat who rose to prominence in the 1970s as a reformist governor emblematic of a new wave of Southern leaders and then served four terms in the U.S. Senate, where he was known for his oratorical skills and political independence, died Jan. 1 at his home in Little Rock. He was 90.

The cause was complications from Alzheimer’s disease and a broken hip, said his son Bill Bumpers.

A former trial lawyer in the Ozark foothills, Mr. Bumpers triumphed over a set of formidable Arkansas politicians, including Winthrop Rockefeller and J. William Fulbright, to launch his career.

As governor from 1971 to 1975 and then senator until 1999, he displayed masterful technique as a public speaker that was a key to his success. “Funny as all get-out and could talk an owl out of a tree,” another Arkansas politician, President Bill Clinton, once observed.

Whether on the Senate floor or in an Arkansas town square, Mr. Bumpers clothed his advocacy in entertaining stories and colorful colloquialisms. An opponent’s argument would be “thin as spit on a rock,” a misguided proposal likely to cause “deficits big enough to choke a mule.”

Mr. Bumpers in 1995. (Ray Lustig/The Washington Post)

A proponent of arms control — he quipped that President Ronald Reagan did not want “to spend money on anything that does not explode” — Mr. Bumpers pushed to cut funding for a range of weapons and antimissile systems.

Clinton drew on Mr. Bumpers’s talents in his 1999 impeachment trial, tapping his home-state ally to join his legal defense team and make the closing arguments against perjury and obstruction of justice charges stemming from the Monica Lewinsky affair.

The speech, delivered in the Senate less than a month after Mr. Bumpers had left the body, won praise as an eloquent defense of the president on constitutional grounds, leavened with disarming humor.

“You can take some comfort, colleagues, in the fact that I am not being paid, and when I finish, you will probably think the White House got its money’s worth,” he said.

In 1970, the highest elective office he had held was a local school board seat. But he came out of political nowhere that year to win the governorship, defeating former governor and segregationist Orval Faubus in the Democratic primary and the sitting incumbent, Rockefeller (R), in the general election. Four years later, Mr. Bumpers dislodged Fulbright (D), a five-term incumbent, and moved to the Senate.

As governor, Mr. Bumpers raised income taxes for top-bracket earners, increased teachers’ salaries and streamlined the state’s overgrown bureaucracy. He achieved national attention as one of a new, progressive breed of Southern governors, a group that included Georgia’s Jimmy Carter, and there was talk that he could be a presidential contender — a step he considered taking in 1976 and again in the 1980s but never did.

In Washington, Mr. Bumpers was known for bucking the conservative winds blowing across his state. A steadfast opponent of efforts to amend the Constitution, he voted against proposals to ban flag desecration and permit states to prohibit abortion.

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In 1984, the self-described “Methodist Sunday school boy” was the only Southerner to oppose a proposal to permit prayer in public schools. He argued the move would restrict, not expand, religious freedom.

He considered the Panama Canal issue the hottest of his career. Still in his first term, he voted for the 1978 treaties transferring control of the U.S.-built canal to Panama, putting himself on the wrong side of thousands who contacted his office in opposition to what treaty critics called the “canal giveaway.”

His amiable, down-home personality and reputation for integrity helped lubricate the difficult fit between his Senate votes and opinion at home. “He was a straight shooter, and I think people gave him a lot of credit for being so,” said Hal Bass, political science professor at Ouachita Baptist University in Arkadelphia.

In the Senate, Mr. Bumpers neither chaired a major committee nor acquired an instinct for legislative horse-trading. Instead, he made his mark by going full steam after projects and policies he viewed as out of whack with national needs, common sense or both.

Most notably, he led fights to kill the Superconducting Super Collider, a mammoth proton smasher in Texas that Congress terminated in 1993, and the International Space Station, which survived his perennial attacks.

His causes were not necessarily of a cosmic nature. One of his proudest achievements was winning what colleagues called the third battle of Manassas. In 1988, aroused by Civil War buffs, Mr. Bumpers brought his oratorical might to bear against a commercial development planned for part of the Second Manassas battlefield in Northern Virginia.

After a late-night debate between then-Sen. John W. Warner (R-Va.), who championed the development, and Mr. Bumpers, the Senate backed the Arkansan, 50 to 25.

The common refrain in his crusades was that political and parochial considerations were holding sway over government decision-making at the expense of deficit reduction and spending on education, health and economic opportunity.

Mr. Bumpers, however, found it difficult at times to abide by his own preaching. A member of the Appropriations Committee, he steered millions of federal dollars to Arkansas. In an oral history interview after leaving office, he admitted to forcing the Pentagon to purchase weapons it did not need but on which Arkansas jobs depended, adding, “I was as guilty as anybody.”

Dale Leon Bumpers was born in Charleston, Ark., on Aug. 12, 1925. He cited his father, a hardware store operator who loved politics and admired President Franklin D. Roosevelt, as a lifelong inspiration. His parents were killed in a car accident in 1949.

After serving in the Marines during World War II, he graduated in 1948 from the University of Arkansas and from Northwestern University’s law school in 1951. He then returned to Charleston, set up a one-person law office and served as city attorney.

In his 2003 memoir “The Best Lawyer in a One-Lawyer Town,” Mr. Bumpers told how in 1954 he advised the Charleston school board to immediately implement the U.S. Supreme Court’s landmark ruling against “separate but equal” public schools.

Three years later, when passions inflamed by Faubus’s stand against integration of Little Rock’s Central High threatened to spill over to Charleston, Mr. Bumpers mounted a successful school board race to prevent resegregation of the local system.

His disdain for Faubus’s race-baiting was very much alive in 1970 when the former governor made a bid to regain his old office. The “thought of fulfilling a lifelong ambition and taking Faubus out at the same time was too powerful to resist,” Mr. Bumpers wrote in his book.

With only a losing state legislative race on his political résumé and 1 percent name recognition statewide, he was as dark a horse as a candidate can be. What he had going for him was a pleasing personality, effective television ads and the services of Deloss Walker, a Memphis-based campaign consultant who was experienced in Southern politics. Mr. Bumpers defeated Faubus and that November got 62 percent of the vote against Rockefeller.

In 1974, Mr. Bumpers challenged Fulbright, a fellow Democrat who was chairman of the Senate Foreign Relations Committee and the leading voice against the Vietnam War.

The refined, brainy Fulbright was influential in Washington, but in Arkansas, as the challenger’s polling showed, he was perceived as aloof and highly vulnerable. The largely issueless campaign — Mr. Bumpers privately shared Fulbright’s view of the war — ended in victory for the popular governor by a nearly 2-to-1 margin.

In 1949, Mr. Bumpers married Betty Flanagan, whom he had known since high school. Besides his wife, of Little Rock, survivors include three children, Brent Bumpers and Brooke Bumpers, both of Little Rock, Bill Bumpers of Cabin John, Md.; and seven grandchildren.

After leaving the Senate, Mr. Bumpers joined the Washington law and lobbying firm Arent Fox, where his clients included the University of Arkansas for Medical Sciences and Riceland Foods, a large rice cooperative based in Arkansas.

Mr. Bumpers had an unshakable confidence in his ability to win over listeners — and never passed up an opportunity to try.

Former Senate legislative aide T. Ark Monroe III, now a Little Rock lawyer, recalled driving the senator to a speaking engagement at a Baptist church in the farming community of England, Ark.

On the way, Mr. Bumpers asked for topic suggestions, and Monroe threw out several, adding, “But whatever you do, don’t talk about prayer in school.

“He gets up there in that pulpit, and what does he talk about?” Monroe said. “Prayer in school.”

Brown is a freelance writer.