Together, the two Democrats have already gathered more than $400,000 in campaign dollars, and the primary is still 10 months away. Tuesday marked the deadline for reporting of funds raised from the beginning of the year through June 30.
Up for grabs is the seat held by Assemblyman Gene Mullin, D-South San Francisco, who will be termed out next year.
Hill, who has been a San Mateo County supervisor since 1998, has racked up nearly $242,000 in campaign contributions from 472 donors since the start of 2007. More than $6,800 was his own money. Since he first established his campaign committee last year, Hill has raised nearly $254,000.
Eighty-six percent of Hill's contributions are from sources within San Mateo County, according to his campaign.
"I'm gratified with the broad base of support I've received," said Hill, a San Mateo resident. "The contributions are a balance of many interests in the county. I think that's been my approach to governance and public service."
His donors also include many developers. Of Hill's top 32 contributors who put in $2,500 or more this reporting period (the maximum allowed by law is $3,600), nearly half are involved in development, construction or real estate. The group includes heavy hitters like the David D. Bohannon Organization, which built Hillsdale Shopping Center in San Mateo, and the Bay Meadows Land Company LLC, which is set to turn the Bay Meadows Race Track into an 83-acre development.
Contributors also include county employees, such as Sheriff Greg Munks, who gave $3,000, and members of several city councils within the district.
Despite the big dollars, Hill's camp was quick to report that 37 percent of the contributions were $100 or less.
Holober, who is the executive director of the Consumer Federation of California and a trustee of the San Mateo County Community College District, has taken a different approach to fundraising. While he has close to $209,000 in cash for his campaign as of June 30, his coffers are largely buoyed by a $100,000 loan from himself. He has also given $64,000 of his own money to the campaign, leaving him with just over $47,000 raised in contributions from others since his committee was established in 2005. Holober raised more than $37,000 in contributions from others this year.
"I'm working hard on doing outreach to voters," said Holober, a Millbrae resident. "I'm also doing outreach to donors, and I believe we're on track to raise the money that's needed."
Holober's largest campaign supporter by far has been labor. Out of 82 donors who have contributed since last year, more than 25 percent have been labor unions or their political action committees.
"My campaign is about rebuilding the middle class, protecting consumers and education reform," Holober said. "Those are issues that resonate with working families. I'm proud to have the support of working people and their organizations."
Holober is endorsed by several strong labor unions in the state, such as the California Nurses Association and two locals of the California Federation of Teachers. He was also endorsed earlier this year by U.S. Sen. Barbara Boxer.
In this heavily Democratic county, races for seats in the state Legislature are by and large decided by the June primary.
On the Republican side, Elsie Gufler, a Realtor from Millbrae, has officially thrown her hat into the race. Gufler also made an unsuccessful attempt to unseat Mullin when he ran for re-election in 2006. Campaign finance data for Gufler, who has accepted spending limits, were not filed Tuesday.
Still unknown is whether Millbrae Councilwoman Gina Papan will throw her hat into the ring. Papan, a Democrat who made an unsuccessful bid for the Assembly seat against Mullin in 2002, did not return a call seeking comment.