What to know about Montana Republican Greg Gianforte

— -- Montana special election candidate Greg Gianforte is making headlines for allegedly "body-slamming" a reporter Wednesday night.

Gianforte has been charged with misdemeanor assault under Montana state law for apparently attacking Guardian reporter Ben Jacobs at his Bozeman, Montana, campaign headquarters.

The Montana Republican is facing off against Democratic populist singer-songwriter Rob Quist for the seat vacated by now-Interior Secretary Ryan Zinke. Democrats have been hoping for a surprise victory in the GOP-leaning state.

So who is Greg Gianforte? Here's what you need to know:

The basics

Greg Gianforte is the Republican candidate for the special election for the U.S. House seat in Montana. He is a former technology and software company executive who unsuccessfully ran for governor in 2016. He's been married to his wife, Susan, for 28 years and has four children.

The making of a millionaire

Gianforte founded Brightwork Development in 1986 and sold the business eight years later. He retired at 33, according to Inc. magazine, and moved to Bozeman, Montana. "I fell in love with Montana nearly 40 years ago when I first came to Montana on a school trip," Gianforte writes on his campaign website.

“After realizing that he couldn’t spend the rest of his life fly-fishing,” the multi-millionaire founded another technology company, RightNow Technologies, in Bozeman, according to Inc.

The business created over 500 jobs, according to his campaign website. He sold RightNow Technologies in 2011.

Political history

Gianforte ran unsuccessfully for governor in November, falling to incumbent Democratic Gov. Steve Bullock by a 50-46 percent margin. President Donald Trump won the state by more than 20 percentage points.

Gianforte secured the nomination for the U.S. House seat on the first ballot of a party nominating convention.

He has come under scrutiny during his campaign for owning shares in Russian companies that have been sanctioned by the U.S. government, according to The Guardian. The holdings total nearly $250,000.

His assets range between $96 million and $328 million, according to The Associated Press.

Gianforte has been supportive of major pieces of Trump’s agenda, such as health care reform and his travel ban. Gianforte also backed Trump's decision to fire FBI Director James Comey.

The Billings Gazette reports Gianforte is known for his involvement with an affiliate of Focus on the Family, a conservative Christian radio organization.

'Body-slamming'

Gianforte allegedly "body-slammed" reporter Ben Jacobs on Wednesday before an interview with Fox News after Jacobs repeatedly asked him questions about his support for the Republican health care plan. "Gianforte grabbed Jacobs by the neck with both hands and slammed him into the ground behind him," Fox News reporter Alicia Acuna wrote in an article on Wednesday.

"I'm sick and tired of you guys," Gianforte can be heard saying on an audio recording released by The Guardian. "The last guy who came in here ... did the same thing. Get the hell out of here."

"I went from being vertical one moment to being horizontal the next," Jacobs said this morning on "Good Morning America." "It became something that turned on a dime into the type of encounter I never expected to have with a politician and one that's very disappointing for what it means for the press."

Gianforte has been charged with misdemeanor assault.

ABC News' Adam Kelsey contributed to this report.