The Senate’s most prolific fundraiser has been equally aggressive about taking full advantage of new rules that doubled the amount of money an individual can contribute to federal campaigns.

Sen. Charles Schumer (D-N.Y.), who collected $1.5 million in the first three months of 2003 and is sitting on $14.8 million in his campaign treasury, had 190 donors “max out” in that brief period — meaning they have hit the $4,000 limit in contributions they can make to his 2004 campaign.

Schumer reported receiving about 1,320 contributions greater than $250 in this three-month period alone, and the top donors were apparently not fazed by the higher ceiling on campaign giving. In fact, a dozen Schumer donors were so exuberant that, according to the Senator’s latest campaign finance statement, they inadvertently exceeded the $4,000 contribution limit — temporarily at least — by ponying up a total of $6,000 each for the election cycle.

Alert Schumer campaign staffers promptly provided $2,000 refunds before running afoul of the Federal Election Commission.

Meanwhile, hundreds of other Schumer donors have already given more than $2,000, making them excellent candidates to max out before Election Day 2004.

In their effort to scare off all top-tier opposition — and they are succeeding spectacularly so far — the Schumer forces are apparently making an effort to get supporters to contribute early and often.

Schumer’s campaign office in New York on Wednesday referred calls about fundraising to the Senator’s Capitol Hill spokesman, Phil Singer. Singer said he would have someone connected to the campaign respond, but no one ever did.

Under the new law, individuals can now give $4,000 to candidates for federal office — $2,000 for the primary and $2,000 for the general election. While it’s too soon to say how many of these campaigns have donors who maxed out, a Roll Call analysis of 2004 Senate races in four large states — New York, California, Pennsylvania and Illinois — showed Schumer far ahead of his colleagues running for re-election.

Sen. Barbara Boxer (D-Calif.), who has banked $2 million so far, had just 29 contributors who have hit the $4,000 limit. A half-dozen Republicans are thinking about entering the Senate race, but so far Boxer has been raising money at a relatively leisurely pace, given the size of the Golden State and the cost of running statewide there.

But Boxer campaign spokesman Roy Behr said the Senator’s fundraising performance this time is consistent with her two previous campaigns.

“Senator Boxer’s fundraising base has always been disproportionately [in] smaller contributions,” he said.

Behr said, however, that the campaign never discourages contributors from maxing out.

“Clearly when people have the means and the willingness to make larger contributions, we encourage them to do so,” he said.

Sen. Arlen Specter (R-Pa.), who is facing a tough primary battle against Rep. Pat Toomey (R-Pa.) but has no general election opponent to speak of so far, had 59 donors max out. Toomey, by contrast, had just four.

Specter also had hundreds of donors who have given $3,000 or more and are almost certain to hit the magic $4,000 figure. One contributor, Robert Asher, chairman of Asher Chocolates in Gwynedd Valley, Pa., curiously fell just $141.71 short.

Specter had $7 million in the bank as of March 31, seven times as much as Toomey.

Illinois is an anomaly. Because millionaire businessman Blair Hull is seeking the Democratic nomination for Senate and has already spent freely from his own wallet, his Democratic primary opponents do not have to abide by the $4,000 limit. Instead, their supporters can write them $6,000 checks for the primary alone.

So far, only state Comptroller Dan Hynes (D) has taken full advantage. According to his campaign finance report, 43 supporters have already written $6,000 checks — a significant percentage of the $897,000 he raised in the first three months of 2003.

While three other primary contenders, former Chicago Board of Education President Gery Chico, state Sen. Barack Obama (D) and health care advocate Joyce Washington have each had large donations — Chico had 15 donors who have each given him $8,000 cumulatively, $6,000 for the primary and the standard $2,000 for the general election — only Hynes has received checks as large as $6,000 for the primary. Another potential candidate, Cook County Treasurer Maria Pappas (D), has yet to create a campaign account with the FEC.

“The folks out there who are supporting Dan are willing to do what it takes to send him to Congress,” said Chris Mather, the Hynes campaign’s communications director.

But the candidate is also not shy about asking for money — even though Mather said he will always ask people for their vote first.

The $6,000 primary cap won’t last in Illinois forever, however. After the close of the second quarterly filing period this year, the FEC will adjust the contribution ceiling — up or down — for the March 2004 primary based on Hull’s contributions to his campaign. A different formula for general election contributions would come into play if Hull won the Democratic primary.

Chris Cillizza contributed to this report.