Associated Press
In this Aug. 4, 2010, file photo President Barack Obama is introduced by AFL-CIO President Richard Trumka before he spoke about jobs and the economy at the AFL-CIO Executive Council in Washington.

Presidential campaign fundraising is taking more of the president's time than at any point in the past four decades, based on President Barack Obama's records of his effort to raise campaign cash.

The presidents Bush were fundraising kings in their first terms in office by at least one measure. George H.W. Bush headlined 109 fundraisers by March 6 of his fourth year in office, and his son attended 134 at the same point in his first term, putting them well ahead of Jimmy Carter and Ronald Reagan and besting Bill Clinton's 96.

President Obama has dwarfed them all, attending 191 events through Tuesday, according to a USA Today story about research done by Brendan Doherty, a political scientist at the U.S. Naval Academy, who has conducted empirical studies for his forthcoming book, "The Rise of the President's Permanent Campaign."

With 10 months left in his term, Obama has already passed the 173 fundraisers George W. Bush attended in his entire first term.

The story said Obama's pace is motivated by rising campaign costs and the fear of super PACs, which unlike in 2008, "can raise and spend unlimited money from corporations, unions and individuals."

"This election raises the possibility that someone will come and drop $10 million, $20 million or $50 million in the race," Binghamton University political scientist Jonathan Krasno told USA Today. "Politicians are at full, hyper-red alert."

Politico reported Monday that Obama has told House Democratic Leader Nancy Pelosi and other Democrats that he won't be able to help them with campaign cash like he did four years ago, a sign that he either isn't raising as much as anticipated or not worried about mega-donations, or both.

Last month, Obama reversed his position on super PACs. He dropped his pledge not to use super PACs, signaling to major Democratic donors that they should support his re-election campaign through PACs, the New York Times reported.

“We’re not going to fight this fight with one hand tied behind our back,” Jim Messina, the manager of Obama’s re-election campaign, told the Times. “With so much at stake, we can’t allow for two sets of rules. Democrats can’t be unilaterally disarmed.”