Story highlights Before Gianforte's choke-slam on Jacobs, the race had been tightening due to the corroding national environment for Republicans

Speaker Paul Ryan said Thursday that Gianforte should apologize

Washington (CNN) Greg Gianforte's choke-slam of reporter Ben Jacobs on Wednesday night -- and the ensuing assault charge -- might not cost him a victory in today's Montana special election. But even if Gianforte wins, Republicans will face a major decision on whether or not to seat him.

What's beyond debate is that, according to Jacobs and multiple eyewitnesses , Gianforte grabbed the reporter by the throat and threw him to the ground -- screaming "sick and tired of you guys ... get the hell out of here."

While Gianforte's campaign put out a statement -- ludicrous on its face -- blaming Jacobs for his "aggressive" reporting tactics, the Gallatin County Sheriff's Office decided that the evidence was clear, charging the Montana Republican nominee with misdemeanor assault.

It's totally possible -- despite the fact that Gianforte's assault charge is splashed across the front pages of Montana's newspapers and leading many national newscasts this morning -- that he still wins the election today.

Montana is typically a Republican state at the federal level; President Donald Trump carried the state by 20 points in 2016. (Montana has only one House district, so today's race will decide the representative for the whole state.) It is also a state where you can vote by mail -- and, according to figures from the secretary of state, more than 250,000 ballots had already been returned as of Tuesday. That's roughly seven in 10 of all ballots election officials expect to be cast. (In the 2016 general election, just north of 507,000 votes were cast .)

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