The 2014 midterms are just two and a half weeks away. Here at Vox, we've been extensively covering what the various election forecasters are predicting. But here's a more unscientific overview of what's going on in the key races, ranked by which ones seem closest and most crucial to determining which party will win control of the chamber.
1) Kansas: Greg Orman (I) vs. Sen. Pat Roberts (R)
The bizarre and unexpectedly-competitive race in Kansas pits longtime, 78-year old incumbent Pat Roberts against independent Greg Orman, a businessman. Orman has said that he'll caucus with whichever party wins a majority. If he's serious about that, the outcome of his race will only matter if the Senate ends up evenly divided (50 seats won by Republicans and 49 won by Democrats). However, his positions and financial backers seem to indicate he'd be more at home in the Democratic caucus.
In the weeks after Democratic nominee Chad Taylor dropped out of the race at the behest of national Democrats, Orman consistently led every poll pitting the candidates against each other head-to-head. But recently, Roberts has retaken the lead in a few polls, showing the race is far from over.
The Kansas race is so crucial because, if Roberts wasn't trailing, the GOP would have an easy path to a Senate majority by winning only seats in deeply conservative states. Further victories in purple states like Iowa, Colorado, and North Carolina wouldn't be necessary, except to pad their majority. If Orman pulls it off, though, the GOP would need to win one of those three purple state seats — or win over Orman himself — to secure their majority.
2) Iowa: Rep. Bruce Braley (D) vs. Joni Ernst (R)
Democrats have had a difficult time locking down the Iowa open Senate seat. Their candidate, Rep. Bruce Braley, was caught on camera making fun of Sen. Chuck Grassley for not having a law degree, and has been criticized for his behavior in a strange episode involving a neighbor's chickens walking onto his property. (Through an intermediary, Braley communicated to the neighbor that he wanted to "avoid a litigious situation" regarding the trespassing chickens. The chickens' owner criticized his approach as "not neighborly.")
Meanwhile, GOP challenger Joni Ernst has a unique profile as a lieutenant colonel in the Iowa Army National Guard, but has been criticized for flirting with far-right views on several issues, including nullification of federal laws and impeaching President Obama. Democrats hope Iowans will eventually decide Ernst is too extreme for them, but it's far from clear that will happen. This is a state that's voted for both Barack Obama and Chuck Grassley, after all. If the GOP wins the red state races and Ernst wins in Iowa, they're highly likely to win the Senate.
3) Colorado: Sen. Mark Udall (D) vs. Rep. Cory Gardner (R)
For Democrats to have had a good chance of holding the Senate at this point, they really needed incumbent senator Mark Udall to maintain the poll leads he held for most of the summer. Instead, Udall's support has declined, and the GOP nominee Cory Gardner has led 10 out of the last 11 polls.
In some ways, Gardner may seem to have a better shot than Joni Ernst in Iowa — he's cultivated a moderate image, and Democratic attempts to paint him as an extremist haven't worked. But it would be unwise for Republicans to be too confident in the latest numbers — the state's 2010 Senate polling was wrong, giving the victory to GOP candidate Ken Buck, when Senator Michael Bennet ended up edging out a win. Democrats hope that the polls are undercounting Colorado Hispanics — particularly lower-income people who don't speak English, and are more likely to support Democrats.
4) North Carolina: Sen. Kay Hagan (D) vs. Thom Tillis (R)
Senator Kay Hagan is widely viewed as a Democratic bright spot. Despite long being viewed as one of the most vulnerable incumbents this year, Hagan's GOP challenger Thom Tillis hasn't led in any of the most recent 20 polls of the race. Tillis is the speaker of North Carolina's unpopular House of Representatives, and has been attacked over his party's handling of education funding.
But the NRSC isn't yet giving up on Tillis — it reserved $6 million in extra airtime for him recently — and rightly so. Hagan's lead has been consistent but small (it's currently 2.7 percentage points in the HuffPost Pollster average). And Senate candidates posting leads of less than four points in polls three weeks before the election have only ended up winning 62 percent of the time, according to The Upshot's Josh Katz.
5) Georgia: Michelle Nunn (D) vs. David Perdue (R)
We're getting into the more conservative states now — ones where the GOP looks likely to win, yet a loss that would complicate their takeover math is still possible. Georgia is foremost among those states, particularly after Michelle Nunn has taken the lead in the two latest polls. GOP nominee David Perdue has been hobbled recently after Politico reported he said in a years-old deposition that he'd spent "most of my career" outsourcing. Perdue himself said on camera recently that he's "proud" of the outsourcing his business did.
Georgia's been changing demographically, giving the Democrats somewhat better odds than they've had there in the past. And as of Thursday night, Nate Silver ranked it as the second-closest of all the Senate races. But Democrats would be unwise to stake their hopes here, because if Nunn fails to win more than 50 percent of the vote, the race will proceed to a runoff — in January. That likely means that Democrats will have a tougher time turning out their voters. It also means that if control of the Senate hangs in the balance, the race would be nationalized — and Georgia's conservative-leaning electorate would be repeatedly informed that if they vote for Nunn, they'd be ensuring that Harry Reid would remain Senate Majority Leader.
6) Alaska: Senator Mark Begich (D) vs. Dan Sullivan (R)
Near the end of the summer, many political analysts believed Senator Mark Begich had run an excellent campaign — the polls were placing him well ahead of his GOP challenger. Now, that's no longer the case. Begich hasn't led in a nonpartisan poll since July, and looks increasingly beleaguered. The partisan gravity of his state appears to have asserted itself.
The HuffPost Pollster average currently puts Begich six points underwater. And things could actually be far worse for him — a recent analysis by Nate Silver found that polling of Alaska is consistently more favorable to Democrats than the state's actual results. Begich will have to hope that his investment in "an expensive, sophisticated political field operation that reaches into tiny villages" — as the Washington Post's Phil Rucker described it — pays off.
7) Arkansas: Sen. Mark Pryor (D) vs. Rep. Tom Cotton (R)
Pryor is another Democratic incumbent in a deep red state who the polls haven't looked good for lately. He's clearly performing a good deal better than his former colleague Blanche Lincoln, who lost to her GOP challenger by 20 points in 2010. But even a well-liked incumbent would have a tough time in a state where Obama and Democrats are so unpopular. His young challenger, Rep. Tom Cotton, a Harvard-educated Army veteran, trailed most polls at the beginning of the year, but has posted consistent leads since.
8) South Dakota: Mike Rounds (R) vs. Rick Weiland (D) vs. Larry Pressler (I)
The odd, three-way race in South Dakota, long written off by Democrats, has gotten renewed attention recently as first campaign finance reformers, and then national Democrats, have announced they'll spend millions on ads there. The GOP nominee, former governor Mike Rounds, has been damaged by a scandal over his administration's handling of an immigration program.
But the race is complicated by the presence of former senator GOP Larry Pressler, who's now running as an independent but holds many Democratic-sounding positions. It's not clear whether Pressler or Democratic nominee Rick Weiland will emerge as the principal challenger to Rounds — or whether they'll split the anti-Rounds vote and ensure his victory.
There's only been one poll since the race started getting national attention. It still showed Rounds ahead — but with a narrow lead of just four points, as millions was about to be spent on ads. Though South Dakota's a conservative state, weird things can happen in a multi-candidate race. With another independent candidate drawing a few points of support, it's possible that the eventual winner will get just 35 percent of the vote. So this is definitely a race to keep following closely.
9) Louisiana: Sen. Mary Landrieu (D) vs. Rep. Bill Cassidy (R)
Things have looked quite grim for Mary Landrieu lately, though we almost certainly won't know her fate on Election Night. Louisiana doesn't have traditional partisan primaries — instead, every candidate runs in a "jungle primary" that takes place on the day of the general election. If no one tops 50 percent of the vote, a runoff pitting the top two candidates will be held in December.
If, as expected, GOP establishment pick Rep. Bill Cassidy gets second place (rather than conservative challenger Rob Maness), he'll face Landrieu in the runoff, when it could be even more difficult to turn out Democratic leaning voters. That's a matchup that's looking pretty bad for Landrieu — she's trailed in seven straight polls. Landrieu also fired her campaign manager last week, which indicates her reelection bid is flailing. Right now, she may be the Democratic incumbent most likely to lose.
Republicans haven't yet given up on New Hampshire, where former Massachusetts senator Scott Brown (R) is challenging Senator Jeanne Shaheen (D). The vast majority of polls still show Shaheen leading, but Brown has led in a couple and seems to have narrowed the gap. And their party's campaign committee hasn't given up on the state yet. But a Brown win is highly unlikely to be decisive for Republicans. If he pulls off a victory, it will likely be because a national tide is boosting the GOP overall and let them take the Senate with room to spare.
Two more formerly-competitive races have fallen off the map lately. In Michigan, the NRSC has canceled planned ads for their candidate Terri Lynn Land, confirming pollsters' estimates that Rep. Gary Peters (D) has built a solid lead there. And in Kentucky, the DSCC has stopped airing ads helping Alison Lundergan Grimes (D), which means Sen. Mitch McConnell is likely to win — and, perhaps, to become the Senate's new majority leader.