Mississippi Sen. Thad Cochran is continuing to grapple with a urinary tract infection that has delayed a planned return to Washington.
The GOP veteran, 79, has been absent from Washington for a month.
Cochran's chief of staff Brad White came as Republicans controlling the Senate had hoped to pass a budget measure that's a key step toward the party's goal of rewriting the tax code. It's unclear whether Cochran's absence will delay the budget debate. Republicans control the Senate with a narrow 52-48 margin.
White said Cochran's wife told him late Saturday that the infection had returned. His office had said last week that Cochran would return to work on Monday.