Republican Sen. John McCain of Arizona speaks on the Senate floor Tuesday. McCain returned to Washington for the first time since being diagnosed with brain cancer.

WASHINGTON — The maverick stood with his party on Tuesday, casting a crucial vote in the Republican drive to repeal “ObamaCare.” But then, like an angry prophet, Sen. John McCain condemned the tribal politics besetting the nation.

Confronting an aggressive brain cancer, the 80-year-old Arizonan served notice he would not vote for the GOP legislation as it stands now. McCain’s impassioned speech held the rapt attention of his colleagues in the Senate chamber.

“Stop listening to the bombastic loudmouths on the radio, television and the Internet,” he intoned. “To hell with them! They don’t want anything done for the public good. Our incapacity is their livelihood.”

A few minutes earlier, McCain dramatically entered the chamber for the pivotal vote, his first since surgery and his cancer diagnosis in Arizona. Unified for once, Republicans and Democrats applauded and whooped for the six-term lawmaker. “Aye,” he said, thumbs up with both hands, for the GOP vote to move ahead on debate.

After he voted, McCain stood at his seat and accepted hugs and handshakes from senators in both parties, drawing laughter from the spectators’ gallery when he and Bernie Sanders exchanged an awkward embrace.

McCain then spoke his mind. His face was pale, cheek bruised, a red scar and stitches above his left eye where doctors had removed a blood clot. But his voice was strong.

He bemoaned the lack of legislative accomplishments in the current Congress and the GOP’s secretive process in working on repealing ObamaCare. He issued a plea for Democrats and Republicans to work together.

Obama and the Democrats shouldn’t have pushed the Affordable Care Act through on party-line votes when they controlled Washington back in 2010, McCain said, “and we shouldn’t do the same with ours. Why don’t we try the old way of legislating in the Senate?”

He blasted the path taken by Republican leaders “coming up with a proposal behind closed doors in consultation with the administration, then springing it on skeptical members, trying to convince them that it was better than nothing.