Mitt Romney, the all-but-declared Republican presidential contender, who has kept his head low for much of the year as he collected cash, raised $10.25 million Monday after bringing together his network of wealthy donors to dial for dollars.

Romney’s team hoped the hefty one-day total would show his strength in the emerging field.

The phone-bank fundraiser at the Las Vegas Convention Center, much like one during his first attempt at the GOP nomination, was the centerpiece of a series of fundraising events that included a conference call with volunteers who were asked to solicit friends and neighbors for donations.

“This is a big kickoff for us, for our fundraising effort. It’s kind of a celebration,” Romney told the more than 400 supporters tuned in to watch him host a brief town-hall-style broadcast on Facebook. “It’s important to me that we get that started, the ball rolling today.”

In truth, the former Massachusetts governor has spent the better part of the year raising money for a campaign he has yet to officially launch. He’s held few political events in recent months, focusing almost entirely on private meetings with donors nationwide.

He wants to emerge from the fundraising quarter that ends June 30 having far outraised his rivals, and displaying financial fortitude in hopes that Republicans will choose him to challenge President Obama. The Democrat shattered fundraising records in 2008 and could raise as much as $1 billion for his reelection campaign.

During his 2008 run for the GOP nomination, Romney used more than $40 million of his own money to pay for campaigns in Iowa and New Hampshire. Victories there never materialized, and Romney ended up losing the nomination to McCain.

Romney launched that bid with a phone-bank fundraiser in Boston in which 400 supporters and Romney raised more than $6.5 million. But while that event was open to reporters, Romney’s camp was much more guarded this time in Las Vegas. Aides refused to allow reporters into the phone bank room, and they wouldn’t say how much his second White House bid would cost.

— Associated Press