Organizers of a petition in support of President Obama's budget plan say they brought more than 640,000 petitions to the Capitol Wednesday, but the number of unique petitions delivered fell considerably short of the reported figure.

Lawmakers are voting on a $3.6 trillion-dollar budget which has drawn fire from both Republicans and some Democrats concerned over the ballooning deficit. 

Democrats fired up their campaign machine several weeks ago to trumpet Obama's budget request, working with the president to tap the grassroots that Obama reached during his campaign. 

Obama taped a Web-based appeal under the New Foundation for Growth banner, and Democrats asked 13 million of his supporters to sign a petition backing his spending plan.

But petition collectors actually got 114,000 signatures off the e-mail request, and another 100,000 from street signatures, FOX News has confirmed. Democrats then made three copies of each petition.

"That's less than 1 percent of their vaunted e-mail list. That's not a high rate of return," one senior Senate GOP leadership aide told FOX News. 

"Every major news organization covered their event two Saturdays ago. They had the president do a Web video. They did training videos," the GOP aide added. "But more people wrote in to ask marijuana questions at the online forum at the White House."

The DNC, however, stands by its number.

"This effort was designed to give our supporters the tools to influence their elected officials," said DNC spokeswoman Natalie Wyeth. "Of course we delivered a pledge to each of their members of Congress -- 642,000 pledges. That's what we said we were delivering and that's what we did."

When asked if she disputed that only a third of 642,000 unique petitions were delivered, Wyeth did not respond. 

FOX News' Trish Turner contributed to this report.