WAYNE — Former Secretary of State Hillary Rodham Clinton and New Jersey Gov. Chris Christie made dueling pitches Thursday in Pennsylvania's race for governor, appealing to voters in a state that could factor into potential 2016 presidential campaigns.

Clinton implored Pennsylvania Democrats to back Tom Wolf's gubernatorial campaign in large numbers, warning against complacency despite his large lead in the polls against Republican Gov. Tom Corbett. “You never know what can happen in an election,” she said.

Without mentioning the polls, Christie gave a nod to the size of the task of changing voters' minds and asked the GOP faithful to volunteer an hour a day doing just that.

The governor's race served as a backdrop for Clinton and Christie, who secured exposure in a state likely to be an important trophy in any 2016 party nomination or general election contest. Both have been filling their schedules with appearances around the country for gubernatorial and Senate candidates.

Clinton is working on drumming up support among female voters while Christie has traveled to about three dozen states as head of the Republican Governors Association, raising millions for the group. Both expect to make a decision on a potential White House bid around the beginning of 2015.

The former first lady made her first appearance for Wolf at an evening “Women for Wolf” rally in downtown Philadelphia's Constitution Center. In her speech, she boosted Wolf as a made-in-America business success who would advocate for women and turn around an education system broken by funding cuts under Corbett.

She also struck a sense of urgency as the campaign enters its final four weeks, suggesting that some voters may “believe the election is over.”

“From my perspective, you can't count on things turning out the way you want them unless you go out and work for it,” said Clinton, who was defeated by Barack Obama in a lengthy 2008 presidential primary campaign.

In an event at Valley Forge Military Academy, Christie cast Corbett as an underdog who has been in this spot before.

Corbett is Pennsylvania's former two-term attorney general from the Pittsburgh area. Wolf, a first-time candidate, spent much of the past three decades running his family's York-based building products distribution business.