As the Democratic nominating battle bears down on Pennsylvania, the state is poised to play a high-profile role in the primary season and put the activism of its voters -- both young and old -- in the national spotlight.

Tucked late in this year's primary calendar, Pennsylvania has traditionally played a bigger role in the general election contest than the nominating process. But with the war of attrition between Sens. Hillary Clinton and Barack Obama still in full swing, Keystone state Democrats are rushing to have their say in selecting the party's nominee.

Pennsylvania has seen a surge in new voter registrations and change-of-party applications over the last several months. Since January, almost 156,000 new voters have registered. More than 100,000 of new voters signed up for the Democratic Party, compared to just over 32,000 for the GOP, according to state data.

Another 134,000 Pennsylvanians switched their party affiliation before the March 24 deadline to vote in the Democratic primary.

Rebecca Holton, spokeswoman for the Pennsylvania Department of State, said that the state is now "nearing the all-time high of registered voters," and that the current 8.2 million is "unusual for a primary."

Candidates and pundits have paid special attention to the state's younger and older voters -- two groups that have been sharply divided between Obama and Clinton, respectively, in earlier state primaries. In Pennsylvania, which ranks third in the U.S. for residents over 65, but boasts more than 100 colleges and universities, the split in earlier contests takes on particular significance.

'Uptick' Spotted in Young Voter Involvement
Both Clinton and Obama are courting young voters -- those between ages 18 and 29 -- by speaking at college campuses or sending campaign surrogates in their stead.

In turn, the students themselves are taking a greater interest in the process.

"I'm seeing huge uptick in involvement," said Rachel Moore, a senior at Lebanon Valley College and president of the Pennsylvania Federation of College Democrats. The group does not endorse candidates in contested primaries. Rather, Moore said, they work with individual schools as well as the state and national parties to register voters, raise awareness of the issues and generate interest in the election.

Marisa Franz and Brian Tashman, co-heads of Bryn Mawr and Haverford Students for Hillary, have also noticed increased enthusiasm among their peers.

"This election has motivated a lot of people to talk about important issues, especially ones that resonate with young voters," the pair wrote in an e-mail.

Genna Selesnick, a freshman at the University of Pennsylvania and publicity director of the school's College Democrats, said that students on her campus "seem very excited and enthusiastic about the election."

The Penn Dems have endorsed Obama in the primary. "He impressed the student organization's members with his dedication to change in both domestic and foreign policy," Selesnick said.

As in earlier contests the call for "change" seems to be a key factor in understanding why so many young voters have flocked to the Obama camp.

"Whenever you start talking about a generational change, it's pretty clear and open that he's appealing to young people to change the course of the history of the country," explains G. Terry Madonna, director of the Center for Politics and Public Affairs at Franklin & Marshall College. "It's a great message for young voters, particularly folks who look at Washington and don't think it's working very well"

Obama's support among youth has helped translate into victories at the polls. In Super Tuesday contests, Obama captured the youth vote in 10 states while Clinton won over young voters in three states, according to the Center for Information and Research on Civic Learning and Engagement.

The youth vote, however, is not wholly skewed in Obama's favor. Lauren McDonnell is in the class of 2009 at Lehigh University, where she is the president of Lehigh for Hillary. "Obama has become the newest fad among college students," McDonnell said. "As strange as it sounds, I almost feel as though many people my age look down on me for not supporting Barack."

McDonnell said she started out as an Obama supporter, but was attracted to Clinton because of the specific plans the candidate has outlined on education issues, such as the Student's Bill of Rights and financial aid.

But, McDonnell said, if Clinton is not the eventual nominee, she will throw her support behind Obama rather than Republican Sen. John McCain. "[McCain] represents a continuation of the present, something that we definitely do not need. Republicans had their eight years to get things done; now it's our turn."

Experience Likely to Resonate With Older Voters
While voters between 18 and 34 represent 25 percent of Pennsylvania's Democratic electorate, the state's seniors -- age 65 or older -- are also expected to play a critical role in determining who wins the primary. Seniors make up 15.1 percent of Pennsylvania's population, and 21 percent of its Democratic electorate.

These older voters, Franklin & Marshall College's Madonna suggests, are not as likely to be lured by a message of "change"; rather, experience seems to be a key factor. Clinton, poised as the "experience" candidate, leads among the demographic.

A Franklin & Marshall College survey conducted in mid-March found that Pennsylvanians 55 and older favor Clinton 55 percent to 29 percent. That helped give her a 6 percent advantage over Obama in the Real Clear Politics average of polls conducted between March 24 and April 2.

"They are much more likely to see the Clinton administration and the eight years of the overall rise in the standard of living, the deficit reduction, and stock market rise as more favorable," Madonna explained. "Her track record, her experience factor here I do think has been a huge help to her in winning seniors."

Sala Udin, coordinator of Pittsburgh African Americans for Obama, has noticed the same trend among the senior voters he's encountered.

"The outreach that we have to seniors is split -- some, especially some elderly black women, still resonate with the first woman that could be elected president of the United States. Some of them still resonate with the Clinton years and how important Bill Clinton was to black people when he was president, so not all of them are as excited as their children and grandchildren about Obama," Udin said.

Madonna and Udin say that while seniors in Pennsylvania are politically active, the organizations they tend to be involved in are non-partisan, such as the NAACP and church groups.

To target seniors, therefore, the candidates have been addressing issues such as health care affordability, prescription drug plans and Medicare.

"This is a campaign about niche market -- different venues, different people, different emphases," Madonna said.

Though comprising a large portion of the electorate, neither the youth nor senior vote alone can ensure a victory in Pennsylvania. In fact, 54 percent of the Democratic electorate, or about 2.2 million voters, fall outside of those demographics.

-- By Candace Nuzzo, Online NewsHour