As the country’s leading conservative donors finished off plates of roast lamb and spaetzle in a Palm Springs, Calif., hotel ballroom on Monday, Charles G. Koch delivered a pep talk.

The November elections had been a major setback for the cause of liberty, Mr. Koch told the more than 200 guests, many of whom had pumped millions of dollars into the political operation founded by Mr. Koch and his brother David. But there would be no backing down, Mr. Koch said, according to some of those attending. They would learn from their mistakes, test new strategies in the coming months and prepare for the 2014 elections, with control of Congress once again at stake.

As the Republican Party grapples with implications of its historic losses last fall, a similar reckoning is unfolding among the deep-pocketed conservatives whose “super PACs” and other organizations spent heavily to defeat President Obama and the Democrats in 2012. Nowhere is the self-examination more unrelenting than within the constellation of advocacy groups, foundations and research organizations nurtured by the Kochs.

“They took this defeat pretty hard and pretty self-critically — which is always a good sign of a vital organization,” said Jack Schuler, a Chicago-area philanthropist and entrepreneur who has been involved in some of the discussions. “I think the dollars will flow if we get a sense that there’s a formula that’s going to work. They don’t like to fund losing causes. The attitude is: Show me this new approach is going to work.”