WASHINGTON — Democratic Sen. Barack Obama, his presidential money apparatus slowed only slightly, raised more than $31 million in April, outdistancing Republican Sen. John McCain, who nevertheless enjoyed his best fundraising month yet.

Obama reported having more than $37 million in the bank at the beginning of May. He moved closer to the Democratic nomination yesterday, but still faces three primaries against a financially weaker Sen. Hillary Rodham Clinton.

McCain raised nearly $18 million in April as his presidential campaign consolidated his fundraising base. He spent only about a third of that, capitalizing on his status as the Republican Party's presidential nominee-in-waiting.

Continuing the expansion of his fundraising network, Obama's campaign reported nearly 1.5 million donors. With such numbers behind him, Obama appears to have access to a continuing flow of money, though his April total was his smallest haul this year. Overall, he has raised close to $265 million for his White House bid.

FIRST TASTE OF RED INK

Obama spent $36 million in April, exceeding his monthly fundraising for the first time. He and Clinton competed in Pennsylvania's April 22 primary, which Obama lost. He also spent heavily during April in Indiana and North Carolina, which held their primaries on May 3. Obama lost Indiana narrowly and won in North Carolina.

Clinton listed cash on hand of nearly $30 million, but more than $22 million is money for the general election that she can't use. She also reported $19.5 million in debts, including $10 million she has lent her campaign. Even without the loan, Clinton was in the red financially for the primary. The loan amount also did not include an extra $1.4 million she put into her campaign in May.

McCain, Obama and Clinton filed their financial data with the Federal Election Commission yesterday.

McCain's finances are an important marker as he moves into direct competition with Obama, who has shown himself to be a fundraiser without equal. McCain has been taking advantage of his status as the all-but-nominated Republican candidate, embracing the big donors from his vanquished foes and putting allies in charge of raising money at the Republican National Committee.

The RNC, which is the party's main political arm, had nearly 10 times more cash on hand than its Democratic counterpart at the end of April, a GOP advantage in what has otherwise been Democratic fundraising dominance this election.

The committee yesterday reported having $40.1 million in the bank. The Democratic National Committee had $4.4 million.

The RNC raised $15.7 million in April compared to $4.7 million by the DNC.

The financial disparity comes in a presidential election year when the candidates rely on the parties to mobilize voters and promote their message. Overall this year, the RNC has raised more than $52 million and the DNC has raised more than $22 million.

PARTY FUNDRAISING

McCain has put his own team at the RNC to operate a Victory Fund Committee that is corralling top Republican donors. Earlier this month, McCain and the party raised $7 million at a fundraiser hosted by New York Jets owner Woody Johnson. The proceeds of that event were not included in the RNC's latest report.

McCain and the RNC are holding a series of upcoming joint events, including one today in Irvine, Calif., hosted by Meg Whitman, who is stepping down as president and CEO of eBay. The event is expected to raise more than $2 million.

Obama has taken his own steps to take over the DNC and assemble a multistate team for the general election, several Democratic officials said yesterday. With such a team in place, the DNC would be able to tap into Obama's prodigious fundraising.

The DNC has lagged in fundraising for some time, a condition made all the more difficult by the Democrats' protracted presidential primary. Top donors have been cheering on either Obama or Clinton and have not turned their attention to the party's needs. Together, Obama and Clinton have raised more than $400 million over the past year and a half, siphoning much of the party money.

Last week, the DNC announced agreements with Obama and Clinton to begin raising money together.

As part of the unusual pact, donors can contribute up to $33,100 to the newly created Democratic White House Victory Fund. The money would benefit whichever candidate becomes the nominee. Some Democrats said the deal would permit some of Clinton's donors to get behind Obama without having to write a check directly to his campaign.

But several Democratic fundraisers said they did not expect the DNC to see much more of an influx of money until June, at the earliest.