Philadelphia District Attorney Seth Williams roamed the parties of the Pennsylvania Society last month, dropping the same line when asked about challengers in his bid this year for a third term.

"The more the merrier," said Williams, sounding chipper at the annual Manhattan political soiree after a year of controversy.

For Williams, a crowded May 16 Democratic primary election ballot may be his best hope for victory.

That was a lesson from the 2009 Democratic primary election for district attorney, when Williams became his party's nominee, winning just 41.75 percent of the vote but defeating four other candidates who split the field.

In Philadelphia, where Democrats hold a 7-1 voter registration edge over Republicans, general election victories are almost always easier than primary wins.

Williams went on to win his first term in the 2009 general election with 75 percent of the vote.

Michael Untermeyer, his Republican opponent in 2009, last week became the fourth Democratic candidate to challenge Williams in the 2017 primary.

U.S. Rep. Robert Brady, chairman of Philadelphia's Democratic City Committee, said Williams' candidacy is "in trouble" but acknowledged a few advantages any incumbent would hold this year.

Brady predicts an "open primary," meaning the city's Democratic Party will offer no endorsement, a rare thing in a city where incumbents usually can count on that support. Democratic ward leaders, Brady said, are unlikely to back Williams this year.

"He's got some problems ahead that I don't know he can fix," Brady said of Williams.

Among those problems:

Williams in August amended his statements of financial interests for 2010 to 2015, listing $160,050 in previously unreported gifts, including home repairs, airfare, and lodgings for vacations, cash, and gift cards, and Eagles sideline passes.

The FBI and IRS, working with a federal grand jury, in 2015 subpoenaed financial records from the political action committee Williams used in his 2005, 2009, and 2013 campaigns.

Those federal investigators in August subpoenaed financial records from the Second Chance Foundation, a nonprofit Williams founded in 2011.

A spokesman for the District Attorney's Office confirmed in August that FBI agents had interviewed staffers there.

A woman romantically linked to Williams entered a diversionary court program in October after admitting she had slashed the tires on two city vehicles parked outside his home in November 2015.

Williams, who has denied any wrongdoing, declined through a campaign spokesman to be interviewed for this article.

Races for district attorney and city controller top the 2017 ballot in what often is referred to in political circles as an "off-year election" because the races draw little voter interest.

In off-year races, support from the party ward infrastructure can be crucial to voter turnout.

Brady sees an advantage for Williams that stands for any incumbent with a recognizable name in a low turnout race.

Voter turnout was just 12 percent for the 2009 primary and general elections.

It was 9 percent for the primary and 12 percent for the general in 2011, when Williams easily won a second term.

The so-called racial math of Philadelphia politics is also on Williams' side, at least for now.

Brady sees an advantage for Williams, who is African American, as long as no other black candidate emerges.

"With him being the only African American, it's just common political sense," Brady said.

Philadelphia Common Pleas Judge Leon Tucker, who is black, called Brady last year expressing an interest in running but then called again to say he would not run.

Tucker, who won reelection to a 10-year term on the bench in 2015, did not respond to requests for comment last week.

Brady said a Tucker candidacy could have been a serious problem for Williams.

Along with Untermeyer, Williams is challenged in the primary by former Managing Director Rich Negrin, former federal prosecutor Joe Khan, and former Municipal Court Judge Teresa Carr Deni.

The Democratic winner this year is likely to face Beth Grossman in the general election. Grossman, a city prosecutor for 21 years, switched party registration from Democratic to Republican last June.

Joe DeFelice, chairman of the Republican City Committee, said he agrees with "the conventional wisdom" that a crowded Democratic primary benefits Williams, but he stopped short of saying he hopes Grossman will face the incumbent.

Still, DeFelice thinks his party can capitalize on the political "baggage" that Williams drags into this election year.

"I think there are opportunities there that didn't exist four years ago and sure as heck didn't exist eight years ago," he said.

DeFelice said Grossman would try to build a coalition of voters.

"If we can corral our base and pick off enough of these disaffected Democrats, in constituencies that are more open to a Republican message, can we possibly tighten up the race?" DeFelice asked, then answered: "Yeah, I think we could. In a perfect world, we could win it."