The top Democrat-friendly super PACs continue to accelerate their fundraising, according to recently filed Federal Election Commission reports, but they remain far behind their GOP counterparts in overall receipts.

Liberal donors such as Reid Hoffman, executive chairman of LinkedIn; venture capitalist Vinod Khosla; Jones Apparel Group Chairman Sidney Kimmel; Minnesota consultant Alida Messinger; Zynga CEO Mark Pincus; and financier George Soros were among the top contributors giving $1 million apiece to Priorities USA Action, according to Political MoneyLine. The super PAC raised $13 million overall between Oct. 1 and Oct. 17.

Majority PAC, which ranks second to Priorities USA Action among Democratic super PACs, raised $9.9 million during the same period. Big donors included Fred Eychaner, chairman of Newsweb Corp., who gave $2 million; Franklin Haney, founder of FLH Co. in Washington, D.C., who donated $1 million; and A.M. Fund President Arnold Hiatt, who contributed $900,000. Both Democratic super PACs also continued to count labor unions among their top contributors.

The top two GOP-friendly PACs, Restore Our Future and American Crossroads, collectively raised $31.7 million from Oct. 1-17, according to Political MoneyLine, less than $9 million more than the $22.9 million that Priorities USA Action and Majority PAC raised together.

Casino mogul Sheldon Adelson continues to top Restore Our Future’s list of big donors; he and his wife, Miriam, gave $10 million to the super PAC. Other big contributors to Restore Our Future in the first half of October were California businessman Jerry Perenchio; investment manager Julian Robertson, and Texas billionaire and Contran Corp. owner Harold Simmons, each of whom gave $1 million.

Simmons also gave another $4 million to American Crossroads, and Perenchio kicked in $500,000 for American Crossroads as well during that period. Additionally, the super PAC collected $1 million apiece from Texas home builder Bob Perry and hedge fund manager T. Boone Pickens.

But in terms of overall receipts, Restore Our Future and American Crossroads have still outraised Priorities USA Action and Majority PAC by more than 2-to-1 in this election. The top two GOP super PACs have pulled in $195.1 million, according to the latest tally from the Center for Responsive Politics, compared with $86.9 million raised by Priorities USA Action and Majority PAC.