Clinton addressed a "Women for Terry" rally Saturday in Falls Church, The Washington Post reported.
The McAuliffe campaign is hitting hard at the Republican nominee, state Attorney General Ken Cuccinellli, depicting him as an extremist on birth control, abortion and divorce.
"I will be a brick wall to stop any efforts to take away your rights," McAuliffe told the crowd.
Clinton said nothing about whether she will seek the presidential nomination in 2016.
She praised McAuliffe as a Democrat who can work with Republicans.
"He has maybe the biggest heart and the most open mind of anyone you will ever meet," Clinton said. "Terry has always been there for me, and I am pleased to be here for him."
For many in the crowd, Clinton was clearly the big draw.
"It's Hillary. I got a chance to see her," Max Booze of Woodbridge, Va., told the Post.
His sister, Amber Aaronstein, said she has volunteered for McAuliffe.
"But obviously, you want to see Hillary," she said.
McAuliffe, a former chairman of the Democratic National Committee and a friend of former President Bill Clinton, raised about $400 million for three Clinton presidential campaigns -- for the president in 1992 and 1996 and his wife in 2008.
Cuccinelli spokesman Richard Cullen said Democrats aren't discussing issues like problems with Obamacare.
"If there was any doubt that Terry McAuliffe would bring Washington, D.C., big-government politics to Richmond, today is your proof," Cullen said.