From Amazon to Walmart, a lengthening list of blue-chip giants of corporate America — long a bastion of G.O.P. money — are pledging to cut off funds to Republicans who opposed certifying the victory of President-elect Joseph R. Biden Jr. An arm of Charles Koch’s political and nonprofit network, which is one of the largest and most influential in conservative circles and spent about $60 million in federal elections last year, said that opposing certification would be a factor that would “weigh heavily” in determining its future spending decisions…

Kenneth G. Langone, the billionaire co-founder of Home Depot and an influential Republican donor who contributed $1 million to a Senate Republican super PAC just two months ago, said he felt “betrayed” by Mr. Trump.

“The biggest mistake anybody is going to make is try and rationalize what happened last week, what the president did and what that crowd did,” Mr. Langone said in an interview on CNBC on Wednesday.