At least eight billionaires contributed to John Hickenlooper’s campaign for U.S. Senate in its first six weeks as the front-running Democrat competed toe-to-toe financially with Republican Sen. Cory Gardner, who also raised millions of dollars between July and September.

Quarterly fundraising reports released late Tuesday show Hickenlooper’s campaign awash in big-dollar donations from wealthy individuals in Colorado and beyond, including billionaires George Kaiser, Christy Walton, Pat Stryker, Laurene Powell Jobs, Kenneth Tuchman, Stewart Resnick, Amos Hostetter and Eli Broad.

Two heirs to the Rockefeller fortune also donated to Hickenlooper, who raised more than $2.1 million in August and September. Former Colorado Gov. Roy Romer and former U.S. Sen. Ken Salazar each gave the maximum amount allowed, $2,800; current Sen. Michael Bennet and his wife did, as well. The Democratic Senatorial Campaign Committee, which has endorsed Hickenlooper, sent him $49,600.

“We’re grateful to have received support from across Colorado for our campaign to bring change to Washington,” Hickenlooper said in a statement his campaign provided last week.

Hickenlooper and other Democrats in the crowded Senate race field are not accepting donations from corporate political action committees. Gardner, a Yuma Republican, is accepting them and received hundreds of thousands of dollars from PACs between July and September.

A PAC run by John Bolton, the former national security adviser, donated $10,000. The National Rifle Association’s PAC handed over $1,000. And several corporate PACs representing industries such as oil and gas, pharmaceuticals, banking, health care, agriculture and alcohol donated.

Gardner, who raised $2.45 million last quarter — $532,655 of which was transferred from other fundraising committees, such as Gardner’s leadership PAC — ended September with nearly $6.7 million on hand. Notable donors include former football star John Elway, members of the Coors family and company, longtime “Entertainment Tonight” host Mary Hart Sugarman and billionaires Richard and Robert Sands.

Gardner doesn’t face a primary challenge, allowing him to continue amassing large sums of money as Hickenlooper and eight other Democrats compete in a primary.

Hickenlooper dominated the Democratic field’s fundraising race last quarter. Andrew Romanoff, a former Colorado House speaker, came in second, raising $503,735. He had $724,597 in his account at the end of September. Romanoff’s donations were considerably smaller than Hickenlooper’s and Gardner’s, and were overwhelmingly from Colorado.

“Our grassroots Colorado Senate campaign has now raised more than $1.4 million — without a dime of PAC money,” Romanoff said on Twitter. He added that “nearly twice as many donations came in September —after the DSCC weighed in against us — as in any other month of the year.”

State Sen. Angela Williams raised $108,293 and had $48,892 on hand at the end of September. Of her total, $8,050 came from out of state and $2,750 of that was from her home state of Oklahoma.

“I look forward to continuing this race into 2020,” Williams said Tuesday. “The amount we raised in the first quarter demonstrates we are emerging as the leading female candidate that remains in the race.”

“When you consider the extreme levels to which the DSCC has gone to put the thumb on the scale for John Hickenlooper, our campaign feels pretty good about our effort,” she added. “Obviously, I know that … our campaign will need to show growth at the end of the year for us to endure.”

Stephany Rose Spaulding raised $41,327 and had $10,638 on hand. Michelle Ferrigno Warren raised $40,839 and had $22,718 in her account. Lorena Garcia raised $25,498 and had $4,531 remaining. Trish Zornio raised $16,384 and had $23,357 on hand. Diana Bray raised $6,514 and had $16,429 remaining. Christopher Milton loaned himself $4,000 and had nearly all of it on hand at the end of September.