Evan Vucci/AP photo

ABC News' Shushannah Walshe and Elizabeth Hartfield report:

The Romney campaign complains that despite the huge fundraising numbers they have brought in-beating the Obama campaign two months in a row-they are actually at a financial disadvantage.

How can that be?

The campaign can only spend primary funds until Romney goes from being the presumptive GOP nominee to the actual nominee at the Republican National Convention next month.

"Besides the fact that we are facing off against an incumbent president who has been able to fully engage in a fundraising battle this entire campaign, as we could not, we are only allowed to spend primary dollars from now through the convention," Romney spokeswoman Andrea Saul in a campaign memo earlier this month.

The Difference Between Primary and General Election Dollars

First of all, we need to explain the distinction of primary and general election dollars. In the primary, the Romney campaign only collected primary donations so they didn't have to refund those funds if he didn't make it past that point (other candidates collect both so their numbers look bigger). Romney did make it to face off against the president and since April he has been collecting general election funds in a joint account with the Republican National Committee called the Romney Victory fund. Those funds cannot be spent until we officially get to the general election after the two conventions next month. If the Romney campaign dips into those funds before the convention, they'll have to refund them later, which is technically legal, but would be a huge headache.

Obama did not have a primary challenge, while Romney had a very competitive primary with GOP money split between many competitors, including Rick Perry, who raised a lot of primary dollars. Because of that difference, there is quite a large disparity in primary funds ( The New York Times estimates about $14.38 million for Romney vs. $84.3 million for Obama) Another important thing to note: Psychologically, Romney fundraisers say that since Romney is now the nominee more GOP donors on the fence are just more willing to give.

So, What's the Answer?

The answer is despite beating the Obama campaign in fundraising in both May and June, the Romney campaign is telling the truth…But that could all change after the convention, and later this week we will get an indication of how the general election funds are shaping up.

In May, the Romney campaign had $16.9 million cash on hand, while the Obama campaign had $109.7 million.

It is a big cash disparity, but we really don't know how big it is and won't until this Friday when the campaigns release the full details about fundraising (cash on hand and spending) for last month.

What we know right now are the top-line numbers for June. The Romney campaign outraised the Obama campaign $106 million to $71 million. In May they also out-raised the president by $17 million. If the Romney campaign continues to out-raise the Obama campaign at this pace, and if they're able to pinch their pennies, so to speak, between now and the end of August, they will be in very good shape come the fall.

Get more pure politics at ABC News.com/Politics and a lighter take on the news at OTUSNews.com