Editor's Note: Introducing the Obameter

Barack Obama has often said Americans need to keep a close eye on their leaders.

"I learned long ago, when working as an organizer on the South Side of Chicago, that when citizens join their voices together, they can hold their leaders accountable," he said in a campaign blog last summer. "I’m not exempt from that. I’m certainly not perfect and expect to be held accountable too."

He made the same point in a September campaign speech on education.

"I want you to hold our government accountable," Obama said. "I want you to hold me accountable."

Okay, we will.

PolitiFact is launching an unprecedented journalistic effort to track Obama’s campaign promises and measure the progress of his presidency. Using our new Obameter, we will track each promise — we’ve identified 510 of them — and rate whether it was kept, broken or compromised. Those ratings will be tallied on our Web site, creating an up-to-the-minute report card on the Obama White House.

We’re also sending our Truth-O-Meter to Washington as we shift the focus of our fact-checking from campaigns to government. We’ll be fact-checking statements by Obama, members of Congress, lobbyists, people who testify before Congress and anyone else who speaks up on the issues of the day.

We’ll use the same approach we used during the presidential campaign. We’ll research the statements and rate them from True to False. The most ridiculous claims will get our lowest rating, Pants on Fire.

For the Obameter, our ambitious new campaign promise initiative, PolitiFact writers Angie Drobnic Holan and Robert Farley have spent the last six weeks digging through Obama’s campaign Web site, position papers, speeches, interviews and debate transcripts. The 510 promises they unearthed is a stunning number, more than Presidents Bill Clinton and George W. Bush combined. (I recognize there are limitations to such comparisons because of differences between our methodology and what other news organizations used in 1992 and 2000. But we believe it’s still accurate to say that Obama has promised considerably more.)

Obama’s promises cover everything from tax cuts to weather forecasting, from ending the Iraq war to educating hunters. Some are quite sweeping (Promise No. 265: "Restore the Great Lakes") while others are very specific (No. 272: "Encourage the use of methane digesters.")

Building on the success of our Truth-O-Meter, we created the Obameter, which will track the progress of each promise and then declare whether it has been fulfilled.

An important point: When we say a promise is broken, that is not necessarily a negative thing or a failure by Obama. The failure to enact a promise might simply reflect that priorities of the Congress or the American people have changed since he made the promise. Or it could indicate that Obama decided there were higher priorities.

I hope you’ll check the site often to see our latest ratings and an up-to-date report card on how Obama is doing. As always, we want your feedback. Tell us if you think we missed any promises that should be included in our database. And we’d also like to hear from you if you believe there’s been progress — or no progress — for a particular promise.

With the Obameter and the improvements to our site, PolitiFact will continue to pioneer new forms of accountability in political journalism. Although we rely on the new technology of the Web to publish our work, our mission remains a simple and traditional one: to empower democracy.