By Steve Holland and Alina Selyukh
WASHINGTON (Reuters) - Republican presidential candidate Mitt Romney and the Republican National Committee raised $101.3 million in July, once again outpacing President Barack Obama and Democrats with a big month of financial strength ahead of the November 6 election.
Obama's campaign and the Democratic National Committee raised $75 million in July, lagging for the third straight month as Democrats brace to witness Obama become the first incumbent to be outspent in the final stretch of the campaign.
Continuing to rely largely on big donors, the Romney campaign, the RNC and state Republican parties involved in the joint fundraising effort had $185.9 million left in cash on hand at the end of last month. Obama's campaign has not disclosed its cash on hand at the end of July.
Overall, Obama and the Democrats are still ahead in the race for cash, having raised about $627 million compared with some $495 million raised by Romney and the Republicans.
But that advantage, typically enjoyed by a sitting president running for re-election, is quickly fading away.
Romney is to be formally nominated as the Republican candidate at the party's convention in Tampa, Florida, this month. At that point, he can begin spending much of his massive haul, so far restricted from use by a campaign finance law, in what is expected to be the most expensive U.S. campaign.
He is running neck-and-neck with Obama in the polls. The former Massachusetts governor will soon announce his vice presidential running mate, which the campaign hopes will provide a boost of enthusiasm for the Republican ticket.
Romney has been boosted by deep-pocketed "Super PAC" allies -- outside groups that can raise unlimited funds and largely help candidates by running negative ads -- who have crushed rival Democratic groups with their financial power.
In June, Romney brought in $106 million, more than Obama's haul of $71 million. At the end of last month, Obama and his allies had about $144 million left in cash on hand, lagging about $26 million behind Romney and his Republican Party allies.
BUILDING UP STAFF AND OFFICES
Although Romney's campaign has also started heavily investing in new staff and offices, the Obama campaign has been spending far more over the past few months, much of it on building and supporting a hefty campaign infrastructure aimed at forming a strong grassroots base in hopes of withstanding the advertising barrage with people power.
In July, more than 94 percent of all donations to Romney and the RNC came in chunks of $250 or less, the Republican campaign said on Monday. But such small donors account for only a quarter of the July cash haul, or $25.7 million, meaning fewer than 6 percent of donors in July gave three-quarters of the cash.
The Republican with a Wall Street background has heavily benefited from the frustrations some financiers have felt with Obama, who has pushed for more regulation of Wall Street after the housing and banking crises.
Obama's campaign said 98 percent of donors in July gave $250 or less, without specifying how much money they account for. But the campaign said an average donation was $53.49.
Until the campaigns submit official federal disclosures on August 20, it is likely to remain unclear how much of the July cash haul went straight to the campaigns as opposed to the national and state parties.
National parties can spend only $21.7 million of their money on coordinated spending with the presidential candidates.
Also, it remains unclear how much of the cash Romney has set aside for the weeks after he and Obama receive official party nominations at conventions in late August and early September.
Campaigns are allowed to accept up to $5,000 from one donor, but only half of that can be spent before the convention.
(Editing by Stacey Joyce and Mohammad Zargham)