HARRISBURG — A combination of retirements and failed redistricting efforts give Democrats in the Pennsylvania Senate an opportunity this month that may not come around again.

And while they are unlikely to erase a 30-20 majority held by Republicans in the state Senate, this could be the beginning of a “two-cycle strategy” that Democrats hope will lift them back into the majority for the first time in more than 20 years. Even gaining just two seats in the chamber would be an accomplishment for a caucus that has not held more than 21 seats at one time since the past century.

And the expectations are high.

“The situation this year allows us to set up for taking the majority in two years,” said Aren Platt, executive director of the Senate Democratic Campaign Committee. “This is really a historic year for us.”

Republicans believe their best chance to win a new seat is in the 35th district, home of state Sen. John Wozniak,

D-Westmont. The state Republican Party has thrown more than $66,000 into the race in the past week, and the Senate Republican Campaign Committee dropped more than $85,000 to help challenger Tim Houser, a funeral director from Ebensburg.

Wozniak’s district is based in Johnstown, which will be ground zero for Pennsylvania’s hottest congressional battle. The expected high turnout in that area will help the incumbent’s chances, Democrats say.

Democratic candidates are challenging Republican-backed policies of the past two years, including cuts to higher education and a natural gas drilling fee that many on the left feel was inadequate.

Republicans are mostly playing defense this cycle, but their candidates for state Senate are reminding voters that the Senate played a key role in restoring funding to higher education after Gov. Tom Corbett called for a second consecutive year of cuts. They also are playing up GOP policies that made Pennsylvania more attractive to businesses, said Senate President Joe Scarnati, R-Jefferson, who also serves as chairman of the Senate Republican Campaign Committee.

“They tend to be running against Gov. Corbett, but he’s not on the ballot – we are,” Scarnati said Friday.

Half of the state Senate is up for re-election every two years. This cycle, Republicans are defending 15 of their 30 seats, including four districts where the incumbent is leaving office.  Democrats have 10 of their 20 members on the ballot.

Republicans have five candidates facing no opposition, while Democrats have four candidates running unopposed. Assuming they all win, the count in the state Senate is 20-14 with 16 contested races.

But only a handful of those are expected to be close battles.

When the state Supreme Court rejected Republican-drawn redistricting maps that would have shored up vulnerable Republican districts, it gave Democrats “a better opening than they would have had, no doubt about that,” said Chris Borick, a pollster and professor at Muhlenberg College in Allentown.

The court ruled that the new state Senate districts will not take effect until at least 2014.

“Having to run under the old seats makes it tougher for our candidates,” Scarnati said, particularly in some of the toss-up districts targeted by the Democrats.

For now, Democrats have pickup opportunities in the 49th district, where incumbent state Sen. Jane Earll, R-Erie, is retiring, and the 37th district, where incumbent state Sen. John Pippy,

R-Allegheny, has done the same.

In Erie, the district is clearly favorable to Democrats despite the fact that Earll, a moderate Republican, won four terms there.

Meanwhile, the 37th district is a toss-up that has become the most expensive legislative race in the state.

In just the past week, the Senate Republican Campaign Committee has dumped more than $200,000 in support of GOP candidate D. Raja, an entrepreneur who started his own tech company. The state Republican Party also has put in more than $10,000, and Raja has added more than $400,000 of his own money, according to campaign finance reports.

On the Democratic side, state Rep. Matt Smith, D-Allegheny, has benefited from more than $12,000 in contributions from various labor unions over the past week as he tries to move up to the state Senate. Senate Minority Leader Jay Costa has chipped in $6,000 as well.

Democrats also are targeting the seat vacated by retiring state Sen. Jeff Piccola, R-Dauphin, in the 15th district and trying to take down incumbent state Sen. Elder Vogel, R-Beaver, in the 47th district.

The Senate Democrats have long been the most obsolete caucus in Pennsylvania state politics.

Since 2000, Democrats have never held more than 21 seats in the 50-seat chamber, and during the national Democratic wave election in 2008, the Pennsylvania Senate was the only legislative body in the nation where Democrats lost seats.

“We’re now running an entirely different operation,” Platt said.

Votes in the state Senate are rarely split on straight party lines, and the chamber prides itself on bipartisanship on many important issues. So Democrats may not need an outright majority to change the internal politics in Harrisburg.

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