HARRISBURG, Pa. (AP) — Eugene DePasquale, Pennsylvania's outgoing state auditor general, has won the Democratic nomination to challenge Republican U.S. Rep. Scott Perry, as vote-counting Friday in primary contests across the state ate up a fourth day.

DePasquale will challenge Perry in the Harrisburg-based 10th District in what many expect will be Pennsylvania's premier congressional contest in this fall's general election. Democrats say they believe they can unseat the four-term Perry, after he won the district by fewer than 3 percentage points in 2018 over a political newcomer.

For Democrats, DePasquale is a top recruit: he won the endorsements of a who's who of top Democratic Party allies.

Plus, the House Democrats' campaign arm, the Democratic Congressional Campaign Committee, added DePasquale in January to its “red to blue” program, in which it gives organizational and fundraising support to top recruits to challenge incumbent Republicans.

Already, the DCCC has reserved $1 million in TV ad time in the Harrisburg market, a committee spokesperson said Friday.

DePasquale beat lawyer Tom Brier, 28, who comes from a politically active family, including an uncle who is married to a sister of U.S. Sen. Bob Casey.

DePasquale is constitutionally barred from seeking another term as Pennsylvania's independently elected fiscal watchdog. He also served three terms in the state House of Representatives, with Perry, and in former Gov. Ed Rendell's administration.

DePasquale, 48, got involved in politics early, as York County's Democratic Party chairman and is the grandson of the late former president of Pittsburgh’s city council, Eugene “Jeep” DePasquale.

Perry, an Iraq war veteran, owns the most conservative voting record in Pennsylvania’s congressional delegation, according to American Conservative Union ratings, and has among the most conservative voting records in the House.

Perry, as a member of the ultra-conservative Freedom Caucus, has been a staunch supporter of President Donald Trump and will benefit from a district that still leans Republican.

Voters there backed Trump in 2016's presidential race by 9 percentage points over Hillary Clinton, and registered Republican voters outnumber Democrats, by about 221,000 to 202,000.

But giving Democrats hope is Perry's comparatively narrower victory in 2018, as well as Gov. Tom Wolf and Casey, both Democrats, beating their 2018 opponents in the district.

Meanwhile, many primary contests across Pennsylvania remained without a clear victor for a fourth straight day Friday, as counties continued to tabulate an avalanche of mailed ballots under the debut of the state’s new vote-by-mail law.

The Associated Press has not yet called a number of races where the contest was close or had a large number of votes yet to be counted, or both.

Those races include several where incumbent state lawmakers trail and the only competitive primary among the statewide races, a six-way Democratic primary contest for auditor general.

More than 1.8 million voters applied for a mail-in or absentee ballot, smashing expectations by state officials and drawing warnings that many contest results would take days to produce. Voters returned about 1.4 million of them, or more than 75%, according to information from the state’s elections office.

Turnout passed 2 million, or 24% of Pennsylvania’s 8.6 million registered voters. Meanwhile, deadlines to accept mailed ballots were extended into next week in Philadelphia and six counties.

By mid-day Friday, 50 counties had completed their mail-ballot counts, and practically all ballots were expected to be counted by the end of Monday, the Department of State said.