A vote that would attach hate crimes legislation as an amendment to a must-pass defense bill is expected Thursday. Republican Senator John McCain of Arizona is leading the charge against the move, Politico reported.

Senate Majority Leader Harry Reid on Tuesday announced he would attach the Matthew Shepard Hate Crimes Act to a $690 billion defense authorization bill. The bill (S909) would add disability, gender and sexual orientation to the list of hate crime protections. The law would also aid state and local governments prosecute hate crimes.

“This week, we'll bring to the floor the Matthew Shepard hate crime legislation, so named in the honor of Judy Shepard's son,” Reid said at a press conference, where he appeared with Judy Shepard, Matthew Shepard's mother.

“Judy Shepard has shown incredible strength, leadership and dedication to bringing justice to America and to her son. She and many others who have suffered taught us that we cannot be afraid to call these crimes what they – hate crimes,” he added.

On Wednesday, McCain led the charge against the move, calling it an “abuse of power.”

“Those of us who oppose this legislation – and it is important legislation – will be faced with a dilemma of choosing between a bill which can harm, in my view, the United States of America and its judicial system and a bill defending the nation,” McCain said on the Senate floor. “I don't think that's fair to any member of this body.”

“I recognize he has strong feelings, well … so do I … I wonder which recent morning did the senator wake up and feel so strongly,” Reid responded. “Where has he been in the past?”

While most Republicans oppose the legislation, other than McCain, senators remained silent on Wednesday as Democrats spoke in support.

“If all that Matthew Shepard had to deal with were taunts about his sexuality, his sexual preference, that would be one thing,” California Senator Barbara Boxer said on the floor. “He had to deal with murderers who tortured him.”

The move will test the brinksmanship of opposing political interests. In favor of more F-22 stealth fighter jets – at a cost of $140 million each – are the Republicans, a provision included in the defense bill. But an expenditure opposed by President Obama, who has urged lawmakers to pass hate crimes. If Democrats succeed in their hate crimes add-on, they will have managed to intertwine the fates of both measures.