In a brief press conference punctuated by several loud rumbles of thunder, losing Mississippi senate candidate Chris McDaniel announced that the campaign is submitting an official challenge of the June runoff election to the state Republican executive committee.

Chris McDaniel is seen in a still from Monday's press conference. (WAFB)

At the outset, McDaniel's lawyer, Mitch Tyner, held up a heavy binder with a triumphant, "This is it" -- the campaign's long-promised evidence of how victory over Sen. Thad Cochran was snatched from its grasp through nefarious means. It's been six weeks, by McDaniel's count, since he lost the runoff campaign for the Republican nomination to the senate to Cochran. Over that time, the campaign has offered sporadic and not-always-consistent explanations for why it feels confident that it will be awarded the nomination.

At Monday's press conference, they clarified. They are submitting the aforementioned binder to the executive committee. They are asking the committee to hold a public hearing on its contents in eight days, or on August 12. "We believe that sunshine on what occurred here will bring about the truth," Tyner said, adding that the campaign has asked that their case "be heard in front of every Republican that wants to be there." Given the enthusiasm gap between McDaniel's supporters -- who appeared at the press conference to interrupt regularly with applause -- and Cochran's (who, justifiably, assume the whole thing is over), a public, packed hearing would almost certainly be awkward for any executive committee members who wanted to challenge McDaniel's case.

So what is that case? The evidence was made available to reporters at the event, but not yet online, so we must take Tyner's explanation as our guide. The campaign had repeatedly argued that it had found more questionable votes through a review of voter rolls than the 7,500 votes that separate McDaniel and Cochran; on Monday, that was revised somewhat. The campaign found 3,500 so-called "crossover" votes, in which Democrats voted in the Democratic primary and then in the Republican run-off. This is understood to be a violation of state law, although it doesn't appear to have been challenged in the past according to experts the Post has spoken with. Whether or not this is cause for those votes to be removed from consideration is unclear, as we've discussed before.

Additionally, the campaign found 9,500 votes where there are questions, presumably about the same issue. And then there are 2,275 improper absentee ballots. If all of those are found to be violations and the executive committee decides to act, it could declare McDaniel the winner. At least according to Team McDaniel. It no longer aims for an (unlikely) jury trial, apparently; it now thinks that the executive committee will simply hand the victory to McDaniel.

But apparently not because of those contested votes. Last week, the campaign gave a preview of its new line of reasoning. In a press release, it argued that the party's rule 11(b) mandates that candidates be elected only with Republican votes. In other words, McDaniel's team likely aims to prove that Cochran's  margin of victory came from Democratic votes, and therefore wasn't a victory at all.

It said as much. "We did some post-election polling," Tyner said, and "71 percent of [Democrats] said they would not support the Republican in the general election." By using some "mathematical regression," he argued, they could toss enough Democratic votes to be declared the winners, by some 25,000 votes.

In other words, the argument goes like this. Democrats voted in the runoff, which, even if it's legal under Mississippi law, is a violation of the party's nominating rules. Given the number of additional votes Cochran received in the runoff -- more than a similar increase seen by McDaniel -- the campaign clearly plans to argue that many of those votes were from Democrats and should be considered invalid. The McDaniel argument will almost certainly focus on the racial make-up of counties that saw an increase in turnout from the primary to the runoff to bolster its argument, which we can predict both because an early draft of its Rule 11(b) press release was explicit about the racial component, and because, last week, this reporter was contacted by Tyner to see if he might serve as an expert witness on the topic. (I declined.)

There are a lot of question marks there and McDaniel's plan requires a lot of dominoes to fall in precisely the right patterns. But McDaniel has never been short on optimism. His campaign still raises the issue of alleged illegal votes, an argument that suffered a blow when their chief witness of vote-buying recanted. (In response to a question, Tyner simply said that vaguely defined illegalities occurred. "Will someone be going to jail?" someone called out from the audience. Tyner demurred.) But it seems unlikely that the executive committee will simply hand a victory to the guy who got fewer votes on election day. In which case, Tyner said, the team was ready to go to court.

"We know that the conservative movement is passionate about this issue," McDaniel said during his brief remarks. "We know the conservative movement is very angry." The crowd roared. With the facts and the law on their side, McDaniel declared that he looked forward to the hearing with the party committee. "The integrity of the election process in the state of Mississippi matters," he said, "but likewise the integrity of the Republican party in its primary system, it matters as well."

"We trust the people to make the right decision," he said at one point. Assuming, that is, that they didn't on election day.