Mitch McConnell, the former Republican Senate majority leader, returned to the Capitol on Monday and cast his first vote after a months‑long absence that fueled rampant speculation about his health.

One of the highest-profile figures in Congress, the 84-year-old senator has been away from the Senate since mid-June, following what his office said was a fall that left him hospitalized. After weeks of silence, that spurred demands for greater transparency and stoked online conspiracies, McConnell disclosed that he had been “briefly unconscious” and “also had to deal with a mild case of pneumonia”. He was discharged from a rehabilitation center last month.

McConnell arrived on Capitol Hill in a wheelchair, and briefly addressed reporters on Monday evening before voting to confirm a federal judge to a district in Ohio.

Appearing frailer, he said he was back to help advance the latest farm bill and to support legislation aiding “our good friends who are totally in the fight against the Russians”.

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The senator, who rarely replies to questions in the Capitol hallways, joked that after years of keeping silent, he wasn’t sure how many reporters would be there to see him return.

“But I’m glad to see you,” he said. “It’s time to get back to work.”

Reporters and photographers were instructed by Senate staff not to take video of his remarks, according to the Associated Press, though still images were allowed.

In a statement released on Monday, McConnell described his recovery as a “long and often frustrating process” compounded by the “lingering effects of childhood polio”.

Alarm over McConnell’s absence came amid a broader debate over term limits and concerns about the advanced age of many US political leaders, which has intensified since Joe Biden abandoned his bid for a second term amid concerns about his fitness to continue serving as president. The initial lack of information about McConnell’s health prompted unusual public intervention from Kentucky’s Democratic governor, Andy Beshear, who published an open letter urging the senator toreassure his constituents.

The longest-serving Senate leader, McConnell will retire at the end of his term in January, and rejected calls to resign before then. He stepped down as the Republican leaderat the end of 2024, and was succeeded by senator John Thune of South Dakota.

McConnell chairs the Senate rules committee and a defense appropriations panel, which is crucial in shaping Pentagon funding, and sits on the agriculture committee.

His prolonged absence complicated the legislative efforts of Republicans, who control the Senate by a narrow 53-47 majority. Over the summer, his absence prevented Republicans from advancing the farm bill – a massive piece of legislation setting agriculture, nutrition and forestry policy – out of the agriculture committee.

Speculation of his imminent return began to bubble when the agriculture committee scheduled a vote to advance the bill for Wednesday, suggesting he would be present to vote the measure through over opposition from Democrats.

“I’m still not quite back to 100%,” McConnell said in the statement released Monday, “but I’ve assured Leader Thune that, as I continue with physical therapy on the advice of my doctors, I will do my best to be present for tough votes when our conference needs me.”