Campbell elaborates in a written statement:

"Every day brings more evidence of the need for fiscal restraint in Washington, and the huge danger to our country from printing money. Truly, in my lifetime, I have never seen the growth of federal government spending more out of control. The consequences will be both inflation in the very near future, affecting us all, but retirees especially, and a tremendous burden on the next generation that will have to pay back what has been borrowed. The federal deficit has more than tripled in a single year. That's suicidal for our country."

Campbell is scheduled to make the announcement in person this morning at the Crowne Plaza Hotel at Los Angeles International Airport.

He will compete for the Republican nomination for senator against Assemblyman Chuck DeVore, R-Irvine, and former Hewlett-Packard CEO Carly Fiorina. Campbell previously served as a member of the House of Representatives representing Silicon Valley communities. He has twice run for U.S. Senate previously.

Campbell had run a low-budget, Internet-based campaign for the GOP gubernatorial nomination against two former Silicon Valley CEOs, Meg Whitman and Steve Poizner, who have each given $19 million of their own money to their campaigns. Campbell would face a lower money wall in the Senate race, although Fiorina has just given her campaign $2.5 million of her own money.

Some analysts believe Campbell's entry into the Senate race will help the conservative DeVore by splitting the moderate Republican vote with Fiorina. And that might bode well for Boxer, who, analysts say, would fare better against a conservative in a Democrat-dominated state. Fiorina's campaign has disputed such an analysis.

Update: GOP gubernatorial candidate Poizner has just released a statement on the Campbell move. It reads:

"In this race, Tom Campbell was never afraid to answer the tough questions, debate the issues, and offer specific ideas for pulling California out of economic crisis. I may not have agreed with all of Tom's proposals, but I admire his attention to policy and his willingness to present detailed specifics. The seriousness of the problems we face demand that our next governor have thoughtful and well-formed plans for bringing California back from the brink. Having served in state government, Tom knows that California cannot be run like a business and the Governor's office is not a boardroom. It was a pleasure to debate Tom Campbell many times on our plans and I wish him the best of luck in the future."

Update: Fiorina spokeswoman Julie Soderlund has also responded in a statement:

"Today Tom Campbell kicked off yet another campaign for yet another office in his never ending quest to get elected again - but using his electoral history as a guide, his kick off tour is more likely to be a farewell tour. Tom's unending quest for statewide office has nothing to do with serving the people of California, rather it's about satisfying Tom Campbell's quixotic personal ambition and the false premise that he will be acceptable to Republican primary voters. California Republicans won't vote for a proponent of higher taxes and more government; they're smarter than Tom Campbell gives them credit for.

"We view Tom's candidacy as an opportunity for Carly to further distinguish herself as a political outsider and fiscal conservative who will always be on the side of the taxpayers - not just for the primary election, but also for the general election. Tom Campbell and Barbara Boxer share many of the same views, not the least of which is their mutual support for increased taxes and government expansion. Running against Tom in the primary provides our campaign an ideal sparring partner for the main event."

Update: DeVore spokesman Joshua Trevino told The Bee:

"The more the merrier. Chuck and Tom don't agree on much. But Chuck's known Tom throughout his entire public life and he respects Tom as a substantive individual although they don't agree on much. The real import of the Campbell entry is the failure of the Fiorina campaign to convince supporters of her inevitability and be sure that Tom Campbell would not be entering this race if Carly Fiorina had not lost the confidence of many of her backers and supporters."

Update: Whitman just released this statement:

"Tom is a man dedicated to public service. We now have three strong Republican contenders vying to become California's next United States Senator, and I look forward to campaigning for victory in November with whomever our nominee is. I am going to ask Tom's early supporters and the rest of our party to join me in the fight to create jobs, cut spending and fix education in California. I'm confident that on Election Day my credentials as a proven job creator and an effective manager will attract the voters we need to win."