MILLIONAIRE BUSINESSMAN Tom Knox has never been elected to anything, and already he's broken a campaign promise.

At a KYW Newsradio debate last week, Knox was asked about criticism from the Committee of Seventy that he was giving the city's new contribution limits a bad rap by pouring so much of his own money into his campaign.

On the air, Knox pledged he would limit his donations to "what I've put in so far."

The commitment lasted less than a week.

On Sunday, Knox contributed another $1 million to the Knox for Mayor campaign, and on Tuesday he added another $250,000, according to campaign finance disclosures filed this week with the city commissioners.

The new money pushed Knox's total contributions to his own campaign to $9.25 million, close to the amount raised by all his rivals combined.

Knox's campaign manager, Josh Morrow, said yesterday that his candidate "must have misspoke" last week when he said he wasn't going to put any more money into his campaign.

"It's a close race and we'll spend what we need to get through the election," Morrow said. "We had a budget we set out when we started 18 months ago, and this is part of it." *