“I knew what the answer was going to be,” Kerrey, a Democrat, said in an interview. “I don’t always know what question not to ask to avoid insulting somebody but, in this case, I did.”

Cash Appeal

Others in Buffett’s inner circle have asked him to increase his giving to Democrats, including Richard Holland, who first invested with the billionaire five decades ago and is the Hassebrook campaign’s other honorary co-chairman.

“I have written him notes asking why the hell he doesn’t” contribute more, Holland said. “I never get a reply.”

In June, Buffett took a step toward big-money giving: His check for $100,000 to Hassebrook’s campaign marked the largest single donation he’s made to a candidate, according to state and federal records. Nebraska state law doesn’t impose campaign contribution limits.

The donation helped Hassebrook raise about $1.4 million, according to state records, and he said he expects to collect enough for his message to break through on television.

“Sometimes those large-money ads work against you,” even if they are produced by friendly super-PACs, said Hassebrook in an interview at his campaign headquarters in an Omaha office park. Voters “see those ads as an implication of who you are and that you’re trying to buy the race.”

Exciting Supporters

The Buffett support has helped excite supporters, said Hassebrook, the former director of the Center for Rural Affairs, a Lyons, Nebraska-based non-profit that advocates for small farms, renewable energy and health care. He left the center after 36 years last August to campaign full-time.

“Warren Buffett is perhaps America’s most respected and effective and brilliant investor,” he said. “When they see him investing in me, it says something to them.”