By Alina Selyukh and Jeff Mason
WASHINGTON (Reuters) - U.S. Republican presidential candidate Mitt Romney raised $106 million in June, far surpassing President Barack Obama's $71 million haul in the record-setting money race leading to the November 6 election.
Romney's fundraising mark, announced by his campaign on Monday, is the best monthly total so far in the 2012 presidential campaign. It is another sign that Romney and his allies are on course to wash away any cash advantage that Obama, as an incumbent president, typically would enjoy in a bid for re-election.
Romney's effort is being fueled largely by big-money donors who have poured cash into his campaign, the Republican National Committee's election funds and independent "Super PACs," or political action committees, that support Republicans.
The former Massachusetts governor and the RNC have raised at least $389 million to date, less than the $512 million Obama has collected for his campaign and the Democratic National Committee, according to federal disclosures and Monday's announcements.
But that gap is narrowing.
In May, the Romney campaign's fundraising - driven in part by events such as a dinner in Las Vegas that was hosted by Donald Trump and raised about $2 million - topped Obama's fundraising for the first time. The June figures reported by the campaigns on Monday continued that trend.
Meanwhile, Romney's efforts are getting a big boost from Republicans' embrace of Super PACs, which unlike campaigns have no limits on how much they can raise from individuals.
Figures for June will not be available until later this month, but through May, Restore Our Future, a pro-Romney Super PAC, had raised more than $61 million. American Crossroads, another conservative Super PAC helping Romney, had raised more than $34 million.
American Crossroads revealed on Monday that it has booked $40 million worth of TV air time in nine key states for the two months leading up to the election.
The PAC supporting Obama, Priorities USA Action, had raised just $14.3 million through the end of May.
Taken together, the fundraising for each side in the presidential race is close, but Romney and the groups that support him are raising money at a faster pace than Obama and his Democratic allies.
The Romney team's fundraising has set off alarms among Democrats at a time when Obama has a slim lead in most polls.
"This is no joke. If we can't keep the money race close, it becomes that much harder to win in November," Obama campaign's chief operating officer Ann Marie Habershaw wrote in an email to supporters, titled "We could lose if this continues."
A 'STATEMENT' BY VOTERS?
Romney's campaign touted the June figures as a sign of his growing momentum and as an indication that its efforts to build grassroots support among small donors are working.
"This month's fundraising is a statement from voters that they want a change of direction in Washington," said Spencer Zwick, Romney's finance chief.
But the figures released by Romney's campaign indicated that nearly 80 percent of the total for June came from just 6 percent of the donations it received - meaning that big-money donors are driving most of the campaign's effort.
About $22.3 million, or roughly one-fifth of the Romney campaign's total for June, came in donations of $250 or less, which generally are seen as a gauge for grassroots support.
That followed a trend in Romney's monthly fundraising reports. In April, about 75 percent of Romney's cash came from 5 percent of his donations. In May, 84 percent of his cash came from 7 percent of his donations.
Federal disclosures show that through the end of May, 11 percent of Romney's donations had come from those who gave $200 or less, according to analysis by the non-partisan Campaign Finance Institute. By comparison, 41 percent of the Obama campaign's donors had given $200 or less.
Obama's campaign has not said how much it raised from such donors in June, but it has said its average donation was $52.54.
A FUNDRAISING RUSH
Campaigns can take in only $2,500 per donor for the primary season, and again for the general election. But the funds the candidates share with the national parties can accept just over $75,000.
Since Romney emerged as the clear Republican nominee in May, he and Obama each have attended dozens of fundraisers where guests have paid as much as $75,000 per ticket.
Romney's latest haul - an estimated $4 million - came over the weekend, from fundraisers in the exclusive Hamptons communities on New York's Long Island. One was at the home of David Koch, a conservative financier who runs oil and gas conglomerate Koch Industries with his brother Charles. Guests paid $50,000 per person or $75,000 per couple.
Obama was to attend two fundraisers on Monday at the Mandarin Hotel in Washington; each expected to attract about 20 attendees paying $40,000 per ticket.
Romney's connections to Wall Street - he is a former private equity executive with an estimated personal fortune of up to $250 million - have helped his fundraising there. So has the frustration that some financiers have felt with Obama, who has pushed for more regulation of Wall Street in light of the housing and banking crises.
Through the end of May, Romney had received $22 million from the finance, insurance and real estate sectors - more than double Obama's $10 million, according to the non-partisan Center for Responsive Politics. In 2008, Obama did much better with such donors, raising $42 million and topping the $31 million raised by his Republican opponent, John McCain.
Romney's haul in June also was helped by the U.S. Supreme Court's ruling that upheld Obama's healthcare law. Romney has said that if he is elected president he will press for repeal of the law, which among other things requires most Americans to have health insurance.
The Romney campaign has said it raised $4.6 million through 47,000 online donations in the 24 hours after the landmark ruling. Obama's campaign also has said it raised a lot of money after the ruling but has not disclosed those figures.
The campaigns are due to officially file their financial disclosures for June by July 20.
(Additional reporting by Alexander Cohen; Editing by David Lindsey and Christopher Wilson)