WASHINGTON — Senator Obama cut back on his spending in June after securing the Democratic presidential nomination, building up his cash on hand as Republican rival Senator McCain outspent him with a heavy dose of television advertising.

Unlike Mr. McCain, who spent more than he raised in June, Mr. Obama accumulated cash during the month, holding back on a ramped-up television campaign until July. Mr. Obama is now matching Mr. McCain’s and the Republican Party’s spending on advertising.

Mr. McCain reported his June fundraising in a monthly report filed Friday with the Federal Election Commission. Mr. Obama has until midnight tonight to file his report.

But Mr. Obama’s campaign announced last week that he raised $52 million in June, more than twice the nearly $21.5 million raised by Mr. McCain during the month. Mr. Obama reported having $72 million cash on hand to Mr. McCain’s $27 million.

Besides raising his own money, Mr. Obama is also encouraging his major contributors to help former Democratic rival Senator Clinton retire her campaign debt. Today, Mrs. Clinton reported having a $25.2 million debt at the end of June, including her own $13.2 million loan to the campaign.

While Mr. McCain reduced his cash on hand from May to June, Mr. Obama increased his by $29 million.

The different financial pictures reflect two distinct strategies by the campaigns. Mr. McCain plans to accept $84 million in public funds for the fall presidential campaign, a move that prevents him from raising or spending any more money above that sum.

Mr. Obama has decided to the bypass the public finance system, the first major party presidential candidate in three decades to do so in the general election. That means Mr. Obama needs to build up his cash reserves going into the fall campaign, whereas Mr. McCain needs to deplete his.

Messrs. Obama and McCain, meanwhile, are still busy raising money. Mr. McCain held fundraisers in the Hamptons in Long Island yesterday and was headed to Maine today for more fundraising and a speech at South Portland. One fundraiser, at the estate of billionaire Ronald Perelman, raised money for the campaign, his joint victory fund with the Republican National Committee and various state parties.

Today, Mrs. Clinton, who suspended her campaign on June 7, reported raising $2.7 million from donors during the month. She also lent her campaign $1 million to pay off some vendors, bringing her total loan to the campaign to $13.2 million.

Mrs. Clinton has continued to raise money and Mr. Obama has asked that his donors help her as well to reduce her debt. Mr. Clinton owed $5.3 million to her senior adviser and pollster Mark Penn, but aides to Mrs. Clinton said she first intends to pay off small vendors owed money by the campaign.

She has until the Democratic national convention at the end of August to raise money to pay off her loan, an unlikely prospect. After that, she can only pay herself back $250,000.

Mrs. Clinton ended her campaign with more than $23 million designated for the general election. She is asking donors whether she can convert that money to the campaign account for her 2012 Senate re-election. Donors can also ask for refunds of that money.