Bob Dole, a presidential hopeful who initially became one of the US senators, has died on Sunday. He was 98.

Dole's family confirmed the saddening news in a statement quoted by CNN, saying he died in his sleep after revealing his Stage 4 lung cancer battle.

"Senator Robert Joseph Dole died early this morning in his sleep. At his death, at age 98, he had served the United States of America faithfully for 79 years," the statement said.

His wife Elizabeth's organization, the Elizabeth Dole Foundation, also shared the same news through its Twitter account.

Although Dole famously served the country as a long-time senator, he also tried winning a seat in higher positions by testing his luck in becoming a Vice President and President of the country. However, he lost the bets in the past years.

His death came after he revealed he had been diagnosed with stage 4 lung cancer in February.

At that time, he released a statement confirming he would receive his first treatment in the same month.

"While I certainly have some hurdles ahead, I also know that I join millions of Americans who face significant health challenges of their own," Dole went on.

President Joe Biden visited him shortly after learning his diagnosis. This time, following Dole's death, the POTUS dropped a message to honor his legacy.

Colleagues, Supporters Pay Tribute To Bob Dole

On Sunday, President Biden described Dole as "one of the greatest of the Greatest Generation." Although they met in politics, they reportedly became friends that he always looked for his guidance.

"I will miss my friend. But I am grateful for the times we shared, and for the friendship Jill and I and our family have built with Liddy and the entire Dole family," he went on.

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Another wrote, "Sincere condolences to the entire Dole Family. Bob Dole will always be remembered as a man who brought honor & respect to America & the Republican Party in America. May you all be comforted in knowing he was highly respected throughout the world. May he rest in peace."

Before his death and cancer diagnosis, Dole struggled with several issues that tested his capacity and health through the years. In 1991, he underwent surgery for his prostate cancer. A decade later, he received a procedure for his abdominal aortic aneurysm.

Meanwhile, in 2005 and 2009, he suffered from a fall in his home and faced leg infection, respectively.

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