U.S. Senate candidate Carly Fiorina used her personal fortune, corporate experience and outsider status to propel herself to the Republican Party's nomination in California.

So far in a young general election, she is holding onto her wallet.

Fiorina lent her campaign $5.5 million before the June 8 primary, but has contributed nothing from her own bank account since and risks losing momentum that has turned the race against incumbent Democratic Sen. Barbara Boxer into a toss-up.

With Fiorina already trailing far behind Boxer in fundraising, any reluctance on her part to self-fund in the general election raises questions about whether she can compete financially.

Federal campaign finance reports released in mid-July showed Boxer with $11.3 million in the bank, compared to Fiorina's $953,000. Boxer's campaign expects to spend $30 million or more on her re-election campaign.

So far, the former Hewlett-Packard Co. chief executive has declined to say whether she will put any more of her own money behind her campaign.

Fiorina routinely sidesteps questions about how much of her own wealth she is willing to put into the race.

Fiorina's reluctance so far to write checks for her general election campaign might in part be due to the size of her fortune.

Fiorina's financial disclosure report filed with the Senate shows that she has assets valued at between $25.6 million and $115.9 million.

Of the $5.5 million Fiorina has lent her campaign, she can repay herself up to $250,000 after the election, according to federal campaign laws.

Money is the lifeblood of all elections, but that's particularly true in California.

Millions of dollars are required to mail fliers and buy the television and radio ads needed to boost a candidate's name recognition with an ethnically diverse electorate that is spread out in a region long enough to stretch from Maine to North Carolina.

Fiorina's campaign is hopeful she will be able to draw on donors nationwide who want to see Boxer defeated in her quest for a fourth Senate term.

Sen. John Cornyn of Texas, the chairman of the National Republican Senatorial Committee, said the assistance the White House has been able to provide Boxer through three fundraisers points to an obvious difference in the race so far.

"They clearly are loading up," he said of Democrats. "It's going to be a tough race, but I do believe it's a winnable race."

Despite his confidence, Cornyn said he was not prepared to say how much help the senatorial committee might provide Fiorina.