Fiorina also raised nearly $1.1 million in donations during her first two months in the race. After expenses, that gives her about $2.7 million going into 2010, according to her campaign.
Fiorina hopes to give California's junior senator her most formidable re-election test, but she will have to survive what could be a challenging Republican primary against state Assemblyman Chuck DeVore.
Fiorina has been vague about how much of her family's money she would put into the race, saying she had no plans to fund it herself. She unveiled a summary of her fundraising to date, but not the entire report covering 2009, which is not due until Jan. 31.
''This is a pivotal time both for California and for the nation, and I am dedicated to the task ahead and in this race to win,'' Fiorina said.
Fiorina is expected to have a clear financial edge against DeVore. Still, she has a lot of work to do to catch up with Boxer, a three-term senator who had nearly $6.4 million in the bank at the end of September.
Former Hewlett-Packard CEO Carly Fiorina loaned $2.5 million of her own money to her campaign for the U.S. Senate, an indication she's willing to invest significant personal resources to unseat Democratic Sen. Barbara Boxer.