But even as McConnell made clear his opposition, the top Republican in the House wasn't giving up on the change in lawmaker pay.
"My position on this is the same," said House GOP Leader Kevin McCarthy (R-CA). "I do not believe Congress should be a place only for millionaires."
At a news conference, McCarthy acknowledged to reporters that McConnell's opposition 'does complicate the path' for a Congressional pay raise, as House leaders may bring the issue to the floor as early as next week.
"This is good news," Sen. Rick Scott (R-FL) said of the public opposition to a pay raise by the Senate Majority Leader.
"No reason Congress should get a pay raise. Now it’s time to pass my bill that would end automatic pay raises entirely," Scott tweeted.
House leaders had planned earlier this month to bring forward a funding bill for the Congress - with no language to block the yearly pay raise - but the bill was yanked from a package of spending bills after concerns were raised by rank-and-file lawmakers.
The plan for now is to try that maneuver next week, which could still create a situation where all House members have to go on the record about pay increase.
Lawmakers earn $174,000 a year; under the plan for a COLA increase, their pay would go up by around $4,500 under this plan.
If they had received yearly increases as provided for under current law for the past ten years, their salaries would be over $200,000.