A bad month for Sen. Mary Landrieu just got a bit worse in the wake of qualifying for her reelection attempt last week. Down in the aggregate in polls entering the month, during it she began falling behind in the money chase, self-inflicted “Air Mary” took off as a campaign issue, and now with the official entries into the contest the hill to climb back to office got steeper still.

In all, nine qualified, including Democrat Landrieu and her main rival Republican Rep. Bill Cassidy, the marginally competitive Republican military retiree/corporate functionary Rob Maness, and six others. Five of them will have no impact on the race. A libertarian will siphon a few votes from Maness, who presents himself as a political outsider, a white male Republican will do the same, two white male Democrats will hardly take from Landrieu, and the same for a black female Democrat.

Her biggest concern comes from the last-minute entry of the Rev. Raymond Brown, the gadfly leader of a New Orleans-based (Landrieu’s stronghold) organization called National Action Now, which once had a disputed relationship with the larger radical civil rights organization National Action Network. Brown has a history of inserting himself into incidents involving presumed racial conflict where the police are involved, most recently (and not for the first time) in New Iberia. In the past Brown has toyed with entering political contests, but committed to this one, at least for now.

Brown, who is black and running as a Democrat, given his notoriety may get one percent of the vote even with minimal campaigning. Add in the other Democrats running and maybe that’s a total of two percent. But the difficulty for Landrieu here is that the majority of those would have voted for her, the rest would not have, and that of the other minor candidates, few of their voters would have voted for Cassidy rather than Maness. In other words, their presence disproportionately harms her compared to Cassidy.

Ordinarily, this would be no big deal because if she failed to win outright, all she has to do is make the runoff, and these couple of points in no way threaten her from doing that. But in this case this is a massive problem for her: while for her the dynamics of the general election – unpopular president of her own party, but if on the ballot still gets her votes disproportionately that in a midterm election don’t show up – aren’t good, those of a general election runoff are even worse. With far fewer contests on the ballot and during the holiday season, disproportionately voters whose demographics favor Republican candidates will participate in that one.

In other words, the Nov. 4 electorate will suit her better than the one of Dec. 6, and her chances of getting 50 percent plus one on the former date are much better than with the latter. So to put it another way, if she cannot get that on Nov. 4, barring incredible circumstances prior to Dec. 6, she has no chance of getting that then.

Simply, Landrieu has to win outright on Nov. 4 or she will not win reelection. That’s why even a two percent swing from her to others may make a crucial difference to her electoral fate, whereas even the presence of Maness makes no real difference to Cassidy’s (unless Maness runs a scorched-earth candidacy that discourages those who vote for him from voting for Cassidy in the runoff). Because her margin for error is critically small in this environment, every little bit matters for her survival, and is why the entrance of Brown into the race, as minimal as his effect will be on peeling off voters, is another blow to her chances and increases the odds in favor of Cassidy’s election.