Gerlach Retirement Opens Up Swing District in Pennsylvania

Representative Jim Gerlach of Pennsylvania, a perennial target for Democrats who covet his suburban district, announced on Monday that he will retire from the House after six terms.

Mr. Gerlach joined a steady trickle of Republican retirements and resignations, including Representatives Jon Runyan of New Jersey, Tom Latham of Iowa, Frank R. Wolf of Virginia and Tim Griffin of Arkansas, whose seats could now be in play. In all, 12 House Republicans have announced that they are stepping down, either immediately or at the end of the year. Democrats have seen just one, Jim Matheson of Utah, announce his retirement; Mr. Matheson’s district is so Republican, his departure is tantamount to ceding a seat.

In a midterm election where the battlefield was expected to be extremely narrow, the fight for control of the House is opening up slightly.

“It is simply time for me to move on to new challenges and to spend more time with my wife and family,” Mr. Gerlach said in a statement. “This is a tremendously difficult decision because I have had the opportunity to work with a multitude of dedicated public servants throughout the years. Together, we have worked to strengthen our communities and create opportunities for the hard-working families we have been privileged to represent.”

For most of his career, Mr. Gerlach has had a tenuous grip on his district, between Philadelphia and Reading, never winning more than 52 percent of the vote. President Obama won it handily in 2008. But after the 2010 redistricting run by ascendent Pennsylvania Republicans, the sixth district became considerably easier for the incumbent. Mitt Romney won 51 percent of the vote in 2012, Mr. Gerlach won 57 percent.

But Democrats vowed Monday to put the district in play. Michael Parrish, a businessman and former Republican, had filed to challenge Mr. Gerlach as a Democrat, and he could face a wide Republican field.

“Though we are losing a strong advocate for Pennsylvania, I have no doubt we will elect another Republican leader in November who will be the same thoughtful lawmaker that Jim is,” said Representative Greg Walden of Oregon, the chairman of the National Republican Congressional Committee.