Reardon, a Democrat, was ahead by 13 percentage points over the Republican state lawmaker, pushing him toward a likely third term in office.
"I'll go to work with the same vigor and the same passion that I have before," Reardon said after arriving at a celebration at Everett's Labor Temple.
Tuesday night's totals showed Reardon with 57,742 votes and Hope with 44,110. That gave Reardon more than 56 percent of the total and Hope about 43 percent.
Reardon sought to play down his apparent victory, cautioning supporters that many more votes are left to count.
Staying on the attack, he also denounced what he called "slimy tactics" from Hope's campaign during these past few weeks.
When someone in the crowd asked whether Hope had conceded the race, Reardon responded with a pun.
"He's very conceited, but has he called me yet?" Reardon said.
Hope did concede at a Republican election-night gathering in Lynnwood. He thanked his supporters and said he was proud of the work building up the local Republican organization for future elections.
"We're content," Hope said later. "We ran hard. We had some successes that came out of this campaign."
He added that he stands ready to help Reardon's administration, either as state lawmaker or in other ways.
"If I can be an ally in any way to help him and the county move forward, I'll do it." he said.
Voting in the all-mail election ended at 8 p.m. Tuesday. That was the deadline to drop off or postmark ballots.
Tuesday's ballot totals were expected to account for about half the final turnout, elections manager Garth Fell said. The county elections office intends to release new totals daily, a process that could last all week or longer.
The Reardon-Hope contest grabbed headlines for mostly negative reasons, with the opponents publicly accusing each other of a lack of ethics.
Things got a little rougher last week when the Washington State Patrol acknowledged an ongoing investigation into Reardon's spending during out-of-town travel on county business. A day before word of the investigation hit the media, Hope's campaign called reporters urging them to look into rumors of the probe.
The investigation was launched after somebody brought concerns about Reardon's domestic travel to the attention of fellow Democrat Dave Somers, the chairman of the County Council. Somers contacted Prosecuting Attorney Mark Roe, also a Democrat, who on Oct. 26 asked patrol detectives to investigate potential official misconduct.
Reardon and Snohomish County Democratic Party Chairman Bill Phillips characterized news of the investigation as a failed last-ditch attempt by the Hope campaign to win the election.
Reardon, on Tuesday, said he had no regrets about the tone of the race. He insisted he only struck after Hope struck first.
Describing himself as a "working-class kid from Everett," Reardon said, "You hit me and I'll hit you back."
Hope also said he had few regrets about how his camp conducted the race. He said he tried to focus on jobs, and tried to point out documented management problems with Reardon's administration.
"Everything we struck on has been factual and true," he said.
Hope said he still wants to push for a county-level office that would investigate issues of professional integrity.
Reardon, who turns 41 later this month, lives in Everett, where he grew up. He served as a state senator and representative before starting his current job eight years ago.
Hope, 36, is a Seattle police officer. He lives in Lake Stevens and is in his second term representing the 44th Legislative District.
Noah Haglund: 425-339-3465, email@example.com.
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