The National Republican Senate Committee ended up donating the maximum contribution to her campaign, but didn't invest heavily in political advertising in Delaware.
But he told the BBC's Today programme that the maximum contribution, equivalent to 8% of earnings, would not produce sufficient pension income to maintain an employee's standard of living in retirement, particularly those on higher salaries.
"But," Mr. Conant added, "we're grateful he gave us the maximum contribution".
Under current law, individual donors can give up to $123,000 to federal candidates over the two-year election cycle, but each candidate can only receive $2,600 -- meaning that a donor can give the maximum contribution to 47 candidates each cycle.
Each year, the maximum contribution would rise with inflation.
The tax law raised the maximum contribution to those accounts to $7,000 this year from $6,500 last year.
The maximum contribution to his campaign, had he taken public financing, would have been $50,000.
Because of the high interest, Charity Wave on Friday increased the maximum contribution allowed to $5,000, from $2,500.
It would also gradually raise the maximum contribution to individual retirement accounts to $5,000 in 2004, from $2,000 currently.
The price of breakfast at the closed press event ranged from $250 to the maximum contribution of $2,700.
