After a heated campaign that drew national attention and millions in outside dollars, Democrat Elissa Slotkin narrowly defeated Republican U.S. Rep. Mike Bishop in Michigan's tightest House election.

Bishop called Slotkin to concede early Wednesday, according to both campaigns.

With all districts reporting, Slotkin had 50.6 percent to Bishop's 46.8 percent, according to unofficial results.

In her victory speech in Clarkston, Slotkin said the mission of her campaign was "to restore some sense of dignity and integrity to our politics."

“This is what happens when you set a goal, and you stay focused, you believe in this country, and that people love it more than anything in the world, and you believe in the possibility of the United States,” she said to shouts and applause from supporters.

"I stand before you tonight a very proud Midwestern Democrat. ... We are practical, we are reasonable, we are independently minded.We are willing to work across the aisle to get something done."

Slotkin of Holly promoted her national-security credentials and seized on the issue of health care to make headway in Michigan’s traditionally GOP-leaning 8th District. She's depicted Bishop as a career politician wedded to the “special interests” that fund his campaigns.

Bishop, the former state Senate leader from Rochester, painted Slotkin as an outsider from Washington supported by Democratic leadership and coastal elites, and who doesn't own property in the district.

The candidates have clashed on health care, qualifications and campaign finance, among other issues.

See more results from the U.S. House races

The district includes Livingston County and parts of Ingham and Oakland counties.

Mary Lindamood, a 54-year-old veterinarian in Howell, said she voted for Slotkin over Bishop, calling the Democratic challenger “very well-prepared” for the job.

Lindamood also voted for Proposal 2, a ballot proposal to create an independent redistricting commission, saying she hopes it will curb gerrymandering in areas like the 8th District.

“We’re not being represented well, and I think getting a nonpartisan group of people to draw more appropriate boundaries is going to be a good thing for Michigan," she said.

Peter Poertner, a 54-year-old firefighter from Howell, said he voted for Bishop and other Republicans because of the economy, which he said he’s “very happy” with.

“Everything was so negative, and I didn’t enjoy that one bit,” he said of the closely watched race.

"However, for me, it's not the negative portion of the race. It’s the individual and how they stand on a particular topic. For me, it’s a conservative stance."

Slotkin had a message to those who didn't vote for her Tuesday.

“Whatever the reason for not supporting me, I want you to know that it is my job to support you. The campaign will stop at the door to my office," she said in her victory speech.

"We will not always agree, but I will always listen."

The contest set a record for spending in a U.S. House race in Michigan at $17 million and growing, besting the $14.15 million set in 2010 in the contest between U.S. Rep. Mark Schauer, D-Battle Creek, and now-Rep. Tim Walberg, R-Tipton, according to tracking by the nonpartisan Michigan Campaign Finance Network.

Both Bishop and Slotkin were born and raised in Michigan.

Slotkin's great-grandfather, a Russian immigrant, founded the family’s meat business, Hygrade Foods, which moved its headquarters to Detroit in 1949 and created the famous Ballpark Franks served at Tiger Stadium.

Slotkin, 42, grew up in Oakland County, spending her early years on her family’s farm in Holly, which is in the 8th District.

She went on to Cornell University in New York and was recruited by the Central Intelligence Agency while in graduate school at Columbia University. She went on to serve three tours in Iraq and later in the White House under both Bush and Obama.

Slotkin moved back to her family’s farm in Holly last year after her senior Pentagon post ended with the Obama administration.

Bishop, 51, attended the University of Michigan and then Detroit College of Law (now Michigan State College of Law) before moving back to his hometown of Rochester, starting a real estate business and law firm.

After his years in the state Legislature, he unsuccessfully ran for Oakland County prosecutor before winning his congressional seat in 2014.

Staff writer Jonathan Oosting contributed

mburke@detroitnews.com