McConnell warned Senate Democrats they would regret the change in the age-old filibuster practices.

Regarding his own action on that fateful Saturday in February when Scalia died, McConnell has not flinched.

His opposition to Garland has been fortified by outside conservative interests, including the longstanding National Rifle Association and newer Judicial Crisis Network, founded in 2004 during George W. Bush administration to promote judicial nominees from the right wing. Carrie Severino, JCN chief counsel and a former Thomas clerk, said this month that it had spent $4.5 million so far on nationwide advertising against Garland.

In the tumult of this election year, the Obama administration has found it difficult to inspire widespread public protest against the Senate refusal to hold even a hearing for the nominee.

After a summer of scant public attention to Garland, Vice President Joe Biden earlier this month visited Capitol Hill to try to spur action. “You don’t have to vote yes, but stand and be counted,” Biden said. “Vote.”

McConnell repeated his no-action pledge.