IN THE MONEY….In some ways, measuring presidential candidates by their fundraising totals is just about the ultimate in political inside pool. The typical American doesn’t know or care how much money a campaign raises — but the numbers are carefully scrutinized by reporters, candidates, staffers, and major donors.

It’s not necessarily fair, and fundraising conditions can change, but candidates who fall behind in fundraising are perceived, usually accurately, as struggling overall. Candidates who fill their coffers well are perceived as credible and strong.

And candidates who raise over $30 million in the second quarter the year before the presidential election are a force to be reckoned with.

Sen. Barack Obama raised $31 million for his presidential primary campaign over the past three months, surging past Sen. Hillary Rodham Clinton’s fundraising machine by nearly $10 million for the quarter to take the lead in contributions in the crowded Democratic field.

Obama became the first Democrat to surpass $30 million in a quarter during a non-election year, a feat his campaign said was accomplished not just with help from wealthy, traditional donors but also with a strong showing among small contributors…. In addition to Obama’s haul for the primary, he collected $1.5 million for the general election, for a total of $32.5 million raised over the past three months.

Hillary Clinton got a fairly significant head start on 2007 fundraising by transferring $10 million from her Senate campaign account — and Obama still surpassed her. Over the first six months of the year, Obama raised nearly $56 million for primary spending, followed by Clinton’s $50 million. Edwards is third with about $22 million, followed by Richardson with roughly $13 million, and Dodd with about $12 million.

Obama’s haul, however, is clearly the big story. Marc Ambinder’s analysis sounds about right to me: “There is no other way to put it: not only did Sen. Barack Obama set a record for single quarter donations by a Democratic candidate, but his fundraising total — $31M from 154,000 new donors — imposes an obligation on all of us who cover the race: we need to figure out why the ‘national’ frontrunner, Hillary Clinton, isn’t generating as much excitement as her chief competitor.”

And what of the fundraising for the Republican presidential candidates? No one in the GOP field has released their numbers yet, but none of the Republicans is expected to be anywhere close to Obama (or Clinton, for that matter).

In the first quarter, all the Dems outraised all the Republicans, $78 million to $53.6 million. This quarter, the disparity should grow even larger.

We’re going to be hearing quite a bit about an “enthusiasm gap” between Clinton and Obama, but let’s also not lose sight of the same gap between Dems and the GOP.

Steve Benen

Follow Steve on Twitter @stevebenen. Steve Benen is a producer at MSNBC's The Rachel Maddow Show. He was the principal contributor to the Washington Monthly's Political Animal blog from August 2008 until January 2012.