HARRISBURG, Pennsylvania — Democratic control of the lower chamber of the state legislature slipped for the second time this session when state Representative Sara Innamorato of Allegheny County announced she had resigned from office to focus on her run for Allegheny County chief executive in November. Her departure means the state House will once again be tied at 101-101.

If you are having a hard time keeping score of how many times power has shifted since January when the legislature was sworn in, the session began with the Republicans holding a slim two-seat majority.

That edge quickly evaporated the following month when the three vacant House seats, caused by one death and two state House members winning higher office, were all won by Democrats in special elections.

However, that power was short-lived. In March, state Representative Mike Zabel resigned under growing pressure from sexual harassment accusers — and the chamber was tied at 101-101.

Six weeks later, Democrats emerged victorious from the special election for Mr. Zabel’s seat, and with that, they regained a slim majority.

Ms. Innamorato said in a statement that leaving now “allows her the opportunity to work with the next representative and fully transition them into the role before the general election in November, ensuring the 21st district has a representative solely focused on advancing the needs of the district.”

It is unclear what bearing her resignation will have on the nearly three-week budget stalemate that neither side is budging on. The special election for that seat will be held on September 19, and the state House is not set to return until a week later.

The seat Ms. Innamorato currently holds weaves through the Allegheny River neighborhoods of the city of Pittsburgh, including the wealthy gentrified neighborhoods of Lawrenceville and the Strip District’s newly high-end residential blocks, along with several northern suburbs, which have flipped from Republican to Democratic in the past few cycles.

Despite the tie, Democrats will still cling to power in the lower chamber — meaning they control the calendar.

Republicans lost a dozen seats and control of the House for the first time in a decade last fall in part because of the way new districts were drawn, favoring urban parts of the state and moving representation away from rural areas, which opened the door for many of their gains.

The GOP was also dragged down by poor candidates at the top of the ticket for governor and U.S. Senate — Doug Mastriano for the former and Dr. Mehmet Oz for the latter.

Creators.com.