WASHINGTON _ Sen. John McCain thanked well-wishers for their support upon hearing he had been diagnosed with brain cancer, saying he would be back "soon."
McCain, who had undergone surgery to remove a blood clot at the Mayo Clinic Hospital in Phoenix and was later found to have brain cancer, tweeted "I greatly appreciate the outpouring of support."
"Unfortunately for my sparring partners, I'll be back soon," the 80-year-old senator said. "Standby."
Numerous elected officials and political figures, including former President Barack Obama and former Secretary of State John Kerry, who like McCain served in Vietnam.
Kerry called McCain "unbeatable, unbreakable" and compared him to President Theodore Roosevelt's speech about the "Man in the Arena."