WASHINGTON (CNN) -- The debate over government spending is heating up on the campaign trail and raising greater focus on which presidential candidate will really change the way Washington does business.

Sen. John McCain has criticized politicians who request millions in so-called earmarks.

But will that sway the American electorate?

Sen. John McCain has been a crusader against so-called earmarks and says his opponent, Sen. Barack Obama, has asked for almost $1 billion in pork-barrel projects for his state in just less than four years in the Senate.

"Nearly a million dollars for every day that he's been in office! And that's change? My friends, don't be fooled," McCain said September 9.

Earmarks are requests for money by a specific legislator, usually for her or his constituency, added onto often-unrelated government spending bills.

According to the nonpartisan watchdog group Taxpayers for Common Sense, Obama has asked for nearly $1 billion in earmarks during his Senate term. But the group gives him credit for disclosing his requests, which most members of Congress don't do.

Obama has not made any requests for the next fiscal year, and even when he was asking for earmarks, he was far from the worst offender, the group says.

"Just to put it into perspective, he got $98 million worth of earmarks in fiscal year 2008. Sen. [Hillary] Clinton got more than $300 million in earmarks, and Sen. [Thad] Cochran, Republican of the [Senate] Appropriations Committee, got $800 million in earmarks," Steve Ellis of Taxpayers for Common Sense said.

Obama's running mate, Sen. Joe Biden of Delaware, doesn't come close to that. But Biden also has never disclosed what he's asked for, until this year. Biden's office said he's requesting about $300 million.

The Obama campaign points out that although McCain hasn't asked for earmarks, his running mate hardly has room to talk. Watch McCain rail against earmarks »

"When you've been taking all these earmarks when it is convenient and then suddenly you're the champion anti-earmark person, that is not change," Obama said Monday.

According to state records and Taxpayers for Common Sense, Alaska Gov. Sarah Palin has asked for about $450 million in federal money since she became governor. But she also gets some credit.

"As governor, she has, by all records, started to reduce the number of earmark requests ... so it's a downward trajectory by our analysis but still significant earmark requests," Ellis said.

Palin also got into the earmarking game early, before she became governor. According to state records and Taxpayers for Common Sense, she helped get about $27 million, some of which went to the small Alaskan town of Wasilla, during her second term as mayor there, from 1998 to 2002.

The watchdog group said one of the reasons was that she hired a lobbying firm run by a former staffer for Sen. Ted Stevens, R-Alaska, one of Washington's most legendary earmarkers.

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