One million dollars a day.

As Democratic Sens. Barack Obama and Hillary Rodham Clinton rushed from presidential contest to contest in January, that was how quickly they burned through their money.

On the Republican side, Sen. John McCain and Mitt Romney were spending a third as much. To see the difference, all a voter in Iowa or New Hampshire or South Carolina had to do was turn on the television.

Of the $30.5 million Obama spent in January, more than $18 million was to place and produce television and radio ads, according to his January report to the Federal Election Commission. For Clinton, who spent a total of $28.5 million in January, $11 million was for ads.

Clinton relied more heavily on direct mail than Obama, spending $3.5 million on mail expenses, compared to Obama who spent less than half of that.

Both campaigns also choose vendors differently. Clinton tends to stay in-house, using her strategists’ firms for major campaign operations. The firm operated by Mark Penn, her senior strategist, received the $3.5 million for direct mail and was also paid more than $315,000 for polling in January. Overall, his firm, Penn, Schoen & Berland, has been paid about $7.5 million so far in the campaign. The campaign also reported that it still owed Penn’s firm $2.1 million

Clinton media strategist Mandy Grunwald’s firm has been paid more than $2 million for producing ads for the campaign.

Obama relies on a number of strategists and consultants for major campaign functions. His polling has been handled by Harstad Strategic Research from Boulder, Colo., David Binder Research from San Francisco, the Benenson Strategy Group from New York and Brilliant Corners of Washington, D.C. The campaign has paid the four pollsters a total of $2.7 million over the length of the campaign.

Obama has paid about $1.2 million for media consulting and media production to the firm run by his senior strategist, David Axelrod. But he has also used other outside consultants for media productions.

The different emphasis offers a glimpse into the two campaign’s strategic decisions.

Obama, the freshman senator from Illinois, needed television to introduce himself to an electorate that did not know him well. Clinton, on the other hand, was a known quantity and used extensive direct mail to reach voters whom Penn had identified as being a part of her voting coalition.

“I bet they felt they could more effectively communicate with people they had identified though a long-term process, which would lead you to making resource decisions about mail,’ said Tad Devine, a Democratic strategist who advised John Kerry’s 2004 presidential campaign.

If the candidates maintain that level of spending heading into the crucial March 4 contests in Ohio and Texas, Obama is likely to have the financial advantage. Clinton was forced to lend her campaign $5 million and still ended the month with $7.6 million in debts. He ended January with $18 million cash on hand and about $1 million in debts.

The difference was Obama’s fundraising explosion in January. He raised $35 million for the primary; she raised $13 million.

McCain, meanwhile, emerged as the all-but-certain Republican nominee, but became embroiled in a dispute with the Federal Election commission. McCain had applied for public matching funds for the primary, but after his nomination became virtually assured, he notified the FEC that he was withdrawing from the public finance system.

This week, the FEC notified McCain that his withdrawal was premature. FEC chairman David Mason, in a letter, told McCain he must first show that he did not use the promise of matching funds to help secure a $4 million line of credit he received late last year. Mason also said the decision to withdraw would have to be approved by at least four members of the six-member commission. That, however, could not happen until the Senate fills four vacancies on the panel.

McCain’s lawyer, former FEC chairman Trevor Potter, said McCain had, indeed, withdrawn and that the FEC could not stop him. He also asserted that the matching funds did not secure the loan.

“We think it’s perfectly legal,” McCain said at a news conference Thursday. “One of our advisers is a former chairman of the FEC, and we are confident that it was an appropriate thing to do.”

McCain needs to stay out of the public finance system because he would otherwise have to abide by spending limits that he is close to reaching now. That would prevent him form spending any money until the Republican national convention in early September.

In the loan agreement with Fidelity & Trust Bank, McCain agreed to secure the loan using his list of contributors, his promise to use that list to raise money to pay off the loan and by taking out a life insurance policy.

But the agreement also said that if McCain were to withdraw from the public financing system and then lose a primary contest by more than 10 percentage points, he would have had to reapply to the FEC for public matching funds and provide the bank additional collateral for the loan.

Two former FEC chairmen not involved with the campaign disagree. Michael Toner said in an interview that it appears the matching funds were not used as security and that McCain has the right to withdraw without a vote of the commissioners.

But Brad Smith, a former chairman of the Federal Election Commission and now a law professor at Capital University Law School in Columbus, Ohio, said the terms of the loan add a new wrinkle to McCain’s effort to bypass the system.

“This new stuff should be very troubling for Senator McCain,” Smith said. “They pledged to go into the public finance system if they thought his funding was going to fail. … That’s strikes me as pretty darn close to pledging them as collateral.”

Still, even if at some point the FEC determines that McCain violated the rules, he would likely face little consequences because he did not accept any of the public funds to which he was entitled.

“What that all makes it is more of a PR problem than anything else,” Smith said.