A senior adviser to President Obama mounted a combative defense of the administration on Sunday, saying that the controversies enveloping the White House were the result of Republican lawmakers trying to “drag Washington into a swamp of partisan fishing expeditions, trumped-up hearings and false allegations.”

The remarks came from Dan Pfeiffer, a member of the president’s inner circle, as he appeared on all five major Sunday morning talk shows in an effort to move the administration past what commentators have described as a “hell week” of controversy and missteps. He pointedly rejected Republican criticisms of the president’s actions and leadership style as “offensive” and “absurd,” and he said the administration would not be distracted from doing the nation’s business.

In his appearances, Mr. Pfeiffer faced often tough questioning over the furors regarding the Internal Revenue Service’s targeted reviews of conservative groups; the lethal attack on an American diplomatic post in Benghazi, Libya, last September; and the Justice Department’s seizure of journalists’ records.