HARRISBURG - It wasn't a light decision. But Debbie McKee had grown to believe that the Republican Party no longer represented her beliefs, and recently switched her registration to Democrat.
"I'm so anti-Bush and Bush politics, I couldn't stand to be a member of that party anymore," said McKee, 57, a retired public school teacher from West Chester who switched just in time for Pennsylvania's April 22 primary.
For state Republicans, voters like McKee could quickly become a problem.
State registration numbers show that since last November, the Democratic Party has gained a whopping 111,227 new voters. In that same time frame, the Republican Party lost 13,391 people from its ranks.
Perhaps even more alarming for the state GOP: Since the beginning of the year, 57,651 residents who were already registered voters - either Republicans, independents, or in any other party - switched to become Democrats. In contrast, only 10,754 already-registered voters filed party-change applications to become Republicans.
Whether it's disillusion with Bush, excitement over the primary race between Hillary Rodham Clinton and Barack Obama, or a deeper shift in sentiment among Pennsylvania voters, registration numbers for Democrats have surged over the last few months.
State Democratic Party officials say that although they would love to take credit, they haven't been making a concerted effort to bolster the Democratic ranks.
That territory, they said, has been ceded to Clinton's and Obama's campaigns, which have been going all out in an effort to sign up voters through highly targeted statewide registration drives.
Republicans have taken notice. They are vowing to work overtime between now and the general election to reverse the trend. Pennsylvania, after all, is a coveted swing state - a crucial battleground - in the general election, and both parties will try hard to capture it.
"We're not wasting any time," said Robert Gleason, chairman of the state Republican Party. "We're going to get them back."
Ken Davis, chairman of the Montgomery County GOP, has set up a Web site, www.votegoppa.com, to lure back Republicans who may have crossed over to the Democratic side.
Gleason said the party also planned to actively court independent voters with a direct-mail campaign and would also target voters who support the losing candidate in the Democratic primary.
"There are going to be a lot of disgruntled voters that may want to come over," he said.
The Obama camp has led the way in many places across the state, including Philadelphia, in getting people to register to vote.
Obama also has been airing radio ads, reminding voters that Monday is the last day to register to vote and urging them to register as Democrats. His army of volunteers routinely sets up registration tables on college campuses and at events from town parades to 76ers games and rallies.
While Clinton's campaign has not run ads, it is launching a major push to sign up new voters. Starting today, her workers will switch into overdrive, setting up shop at train stations, nail salons, malls and coffee shops across the state.
]The Clinton campaign is even bringing Ugly Betty star America Ferrera to the Philadelphia area this weekend to help with the push.
Obama has Caroline Kennedy helping his registration drive this weekend.
To a certain degree, the efforts appear to be paying off.
The most recent statewide registration numbers show a huge uptick in registrations since the beginning of the month, when it became clear that Pennsylvania's primary was going to matter.
In the week beginning March 3, 8,674 people switched parties to become Democrats. The next week, 22,174 people switched parties to become Democrats - 8,100, about 36 percent of them, from Philadelphia, Bucks, Chester, Delaware and Montgomery Counties.
Madeleine Campbell, 32, of Philadelphia, is one of those voters. An independent, she switched her registration to Democrat in order to vote in the primary.
The reason: She's inspired. In her case, it's by Obama. She said her mother, also an independent, has switched her registration.
"I want to make sure my vote counts," said Campbell, a management consultant.
Lou Thieblemont, 62, mayor of Camp Hill, also was a Republican until recently. But he switched to Democrat because he believes that Obama is "the only candidate that speaks to me and my interests."
"Right now, we have a polarized society," said Thieblemont. Obama, he believes, will "get us back to a sane world and use common sense."
Chris Borick, a political science professor at Muhlenberg College, called the surge in Democratic registrations a "cold bucket of water in the face of the state GOP."
He said voting data suggest that while there may be some last-minute switches driven by Obama-Clinton fever, the overall Democratic registration numbers in the state reflected in the last six months are part of a long-term shift of voters away from Republican Party.
"It's a systematic broader trend of the GOP losing voters and the Democrats gaining them," he said.
Not to say the tide won't swing back, said Borick. Democratic voter rolls shrank in the 1980s as a tide of Reagan Democrats swept into the Republican Party.
Of the Republicans this time around, Borick says: "They aren't going to be changing back this year, but maybe next year, or down the road."
Davis, the Montgomery County GOP chairman, said he was not worried yet.
He thinks Republicans who switched will flock back home, and vote for Sen. John McCain in November. He also believes that the primary fight between Obama and Clinton is doing more damage than good.
"Every day that they go on spending money and fighting with each other is another day that we can raise money and get organized," Davis said. "I can't think of a better scenario for the fall."
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