Schwartz, now in her fifth term, on Monday filed paperwork to create a state political-action committee for the 2014 Democratic-primary campaign for governor, effectively declaring her candidacy in the race to replace Gov. Corbett.
She immediately transferred $3.1 million to that account.
Three million of those dollars came from her federal political-action committee, a critical call for Schwartz's future, because federal and state campaign-finance laws make it easy to move that money to the new state PAC, but nearly impossible to send it back to her federal account.
Schwartz has said she will not run for another term in Congress while running for governor, attracting a line of would-be successors.
State Rep. Brendan Boyle of Northeast Philly on Monday became the fourth candidate to file for the Democratic primary to win nomination for the seat.
Boyle cited strong labor support, such as Local 98 of the International Brotherhood of Electrical Workers and Lodge 5 of the Fraternal Order of Police.
Boyle said he has not decided whether he will seek a fourth term in the state House while also running for the 13th District seat.
Boyle joins former City Controller Jonathan Saidel, state Sen. Daylin Leach of Montgomery County and Dr. Valerie Ann Arkoosh, a professor of clinical anesthesiology at the University of Pennsylvania medical school.
Margolies on Monday said "there isn't very much to say" about her plans. She confirmed that she has spoken with area Democratic Party leaders and elected officials, along with her family, but declined to discuss details of those conversations.
U.S. Rep. Bob Brady, the Democratic Party chairman in Philadelphia, said Margolies called and "wanted me to know she's looking at" another run for Congress.
Brady is clearly leaning toward Saidel, describing him as "my dearest friend in the world." He predicted endorsing a Philadelphia candidate and hopes to work out some sort of compromise between Saidel and Boyle.
Saidel is chairman of the political-action committee Schwartz created Monday.
Montgomery County Democratic Party Chairman Marcel Groen said Monday that "Marjorie and I speak all the time," but declined to discuss her interest in the 13th District, noting that Schwartz still holds that seat.