OLYMPIA, Wash. (AP) - Gov. Chris Gregoire's supporters flooded the Democrat with campaign contributions in April, injecting more than $1.3 million into her rematch against Republican challenger Dino Rossi.

With about six months until Election Day, Gregoire's hot fundraising pace in April - more than $44,000 per day - has already made her re-election bid the third most-expensive governor's campaign in state history, behind her and Rossi's 2004 efforts.

Gregoire's geyser of cash was expected, since virtually all of her fundraising this year was been cut off during a January-March freeze on solicitations tied to the legislative session.

Rossi's April haul was more modest, at about $641,000. But his take over the first four months of 2008 still exceeds Gregoire's - he took advantage of her "session freeze" to pile up more than $2.7 million in contributions.

Observers predict the two could wage a $20 million campaign for the governor's mansion, and they're already more than halfway there: Combined, Gregoire and Rossi already have collected more than $10.4 million.

"It's going to disgust us this fall, won't it? ... To see how many ads they'll run," quipped Bryan Jones, a University of Washington political scientist.

Gregoire's chief fundraising event during April was a visit by New Mexico Gov. Bill Richardson, a former Democratic presidential candidate and Clinton administration cabinet officer.

Richardson's speech to a packed Democratic luncheon in downtown Seattle drew about $300,000 for Gregoire's campaign - about $100,000 more than expected, spokesman Aaron Toso said Monday.

"There are a lot of things at stake: health care for a lot of kids, education," Toso said. "People are getting behind that with their pocketbooks."

Gregoire doesn't expect to have another month this big, at least for a while. April was her biggest single-month haul of campaign cash since October 2004, when she took in $1.6 million on the eve of her nail-biting finish against Rossi, Toso said.

Gregoire finally won the 2004 race by a scant 133 votes, following three vote tallies and a failed Republican court challenge.

Rossi campaign officials say they're pleased with their steady fundraising pace. Spokeswoman Jill Strait said Rossi is attracting a flood of new donors, and regularly hears from supporters who didn't cut a check last time because they didn't think he could win in Democrat-leaning Washington.

"We're way ahead of where we thought we would be at this point, and the response around the state has been tremendous," Strait said.

Rossi's ability to stay close with the incumbent Democrat in a left-leaning state, during a bad period nationally for Republicans, shows that GOP financiers are taking the former state senator seriously as a candidate, Jones said.

"I do think it does say something about his very solid, very, very close race four years ago, that maybe this can be put together again," Jones said.