Tuesday is Election Day - for the 4 percent of Philadelphia's population that lives in the state House's 170th District.

A special election is being held to fill that seat, which represents about 65,000 people in Northeast Philadelphia, and was vacated when Brendan Boyle took his seat in the House of Representatives in January.

Democratic ward leaders in the district, led by Lt. Gov. Mike Stack III, in January selected Sarah Del Ricci as their candidate. Her husband, John, is a longtime friend and political ally of Stack's. She founded the Parkwood Therapeutic Riding Center.

Republican ward leaders went with Martina White, a financial adviser.

State House Speaker Mike Turzai, an Allegheny County Republican, decided in early January to hold a special election on Tuesday - just 56 days before the May 19 primary, when Democrats and Republicans will vote for candidates from their respective political parties. Any registered voter in the 170th District can cast a ballot in Tuesday's special election.

The Republican City Committee, which has had some trouble recruiting candidates to run this year, has enthusiastically backed White. The local GOP sees her as having a good chance to add one more seat the Republican majority in the state House.

Democrats have been divided in the district since Boyle's election to Congress last November.

Boyle and his brother, State Rep. Kevin Boyle, wanted Seth Kaplan selected as the candidate. Kaplan has worked for both Boyles at some point.

Kaplan threatened in January to run as an independent, potentially splitting the Democratic vote in the special election, but decided against that.

Democrats have a 7-1 voter registration over Republicans citywide but the advantage is only 2-1 in the 170th.

The polls are open from 7 a.m. to 8 p.m. For information, go to www.philadelphiavotes.com.

215-854-5973 @byChrisBrennan