A crowded primary election day unfolds Tuesday, with voters in six states going to the polls Arkansas, Georgia, Idaho, Kentucky, Oregon and Pennsylvania.
One of the biggest political questions of the year will be answered: Can Senate Minority Leader Mitch McConnell withstand a vigorous Tea Party challenge?
And that's not all. A handful of closely watched House, Senate and gubernatorial primaries are at stake, with results offering critical clues to the direction of the November election and a look at the direction of the Republican Party.
Here are 7 things to watch:
Nearly everyone agrees that Senate Minority Leader Mitch McConnell is on track for a Kentucky GOP primary victory over Tea Party challenger Matt Bevin and several other lesser-known candidates.
It's easy to see why: McConnell ran a focused and close to flawless campaign that seemed to learn from every mistake made by defeated Senate incumbents in recent years. According to the latest Courier-Journal/SurveyUSA poll, McConnell leads Bevin by 55 percent to 35 percent a healthy advantage.
But the final margin matters here: McConnell is, after all, the most powerful Republican in Washington. Winning just 55 percent of his own party's vote is no show of strength particularly for a 30-year veteran of the Senate who has spent more than $11 million on his primary.
While there's no formal threshold for what constitutes a respectable finish for McConnell, if Bevin finishes above 40 percent, that's cause for serious GOP nail-biting about McConnell's chances in the general election. The threat isn't that the anti-McConnell GOP vote will switch to likely Democratic nominee Alison Lundergan Grimes rather, that many of those voters will simply choose to stay home in what could be a close race in November.
House Races To Keep An Eye On
House incumbents have a perfect record so far in 2014: Not a single member in either party has lost in a primary. It's likely that streak will stay intact Tuesday, but there are a few contests to keep an eye on.
The most closely watched House primary takes place in Idaho, where GOP Rep. Mike Simpson is favored to knock off Tea Party challenger Bryan Smith. But the race, once expected to be a barnburner, has proved to be anticlimactic. A traditional conservative and an ally of Speaker John Boehner, Simpson has been the beneficiary of millions in outside spending from groups like the U.S. Chamber of Commerce. Smith's support came from groups like the Club for Growth which, in a sign of Smith's declining fortunes, essentially pulled out of the race last month.
For a sleeper House primary, look to Georgia's suburban Atlanta-based 4th District. It's one of the rare instances this year of a Democratic incumbent getting a competitive primary challenge, with Rep. Hank Johnson facing former DeKalb County Sheriff Tom Brown.
A four-term Democrat, Johnson isn't much of a fundraiser. And he won an anemic 55 percent in his 2010 primary, suggesting he hasn't quite locked down his district.
On the plus side, he's armed with endorsements from the national Democratic establishment among them President Obama and House Minority Leader Nancy Pelosi, and other top House Democratic leaders. But that's another sign of weakness: House Democrats don't typically need to line up and publicize those endorsements. The Obama ask is the surest sign that a Democratic House member is sweating a primary.
Follow The Slime
Oregon Republicans will choose between two Senate candidates with compelling stories. There's state Rep. Jason Conger, who went from homelessness to Harvard Law School, and Dr. Monica Wehby, a pediatric neurosurgeon.
Wehby has captured the imagination of some in the Republican establishment who think a female candidate with her profile is exactly what's needed to win in a blue state like Oregon. But there are many on the right who think Wehby isn't quite conservative enough especially on abortion.
Muddying the waters is a series of opposition research attacks sliming Wehby in the campaign's final week. Twice in the past four days, Wehby has endured damaging news reports about her personal life, including a report that a former boyfriend had accused her of "stalking" him. It's unclear what kind of effect that will have on her chances, but the state's mail-in election system works in her favor: 18 percent of ballots had already been returned through Friday, when the first of the stories broke.
Who Makes The Georgia Senate Runoff?
While the outcome in Georgia's GOP Senate primary is up in the air, one thing seems certain: The nomination is going to be decided in a July 22 runoff.
That's because it's highly unlikely anyone in the crowded field will hit the required 50 percent threshold needed to win the nomination outright Tuesday; in that event, the top two finishers will compete in what amounts to a two-month sprint.
Businessman David Perdue seems likely to take one of the two spots he has led the field in most polls this year. The question is, who gets the other spot? The betting is either Jack Kingston, the veteran congressman with a south Georgia base, or Karen Handel, the former secretary of state who has been endorsed by Sarah Palin and Rick Santorum.
The two conservative, lightning-rod congressmen whose candidacies initially unnerved many Republicans Paul Broun and Phil Gingrey have failed to gain much traction. While their voters are likely to be committed, for one of the two congressmen to advance would likely require an exceptionally low turnout.
The Romney Primary
Mitt Romney is showing no signs of fading away from politics. The 2012 GOP presidential nominee endorsed a handful of candidates in contested primaries across the map Tuesday, among them: Idaho's Rep. Simpson, Rep. Bill Shuster of Pennsylvania and Oregon's Wehby.
Romney isn't the only ex-presidential candidate with skin in the game Bill and Hillary Clinton chose sides in a House Democratic primary in Pennsylvania. They're backing the comeback attempt of former U.S. Rep. Marjorie Margolies in an open Philadelphia-area seat. Margolies is Chelsea Clinton's mother-in-law which explains why the Clintons have helped her raise money and why Bill is featured in one of Margolies' ads.
The Cowboy And The Normal Guy
Until last week, no one outside Idaho was paying attention to its GOP primary for governor. Then came an epic debate Wednesday that was so absurd that it captured national headlines.
One of the two long-shot, fringe candidates who turned the debate into a sideshow framed the race this way in his closing remarks: "Folks, you have a choice. A cowboy, a curmudgeon, a biker or a normal guy. Take your pick."
The dynamics of the primary aren't quite that simple. The debate freak show obscured a surprisingly competitive Tea Party challenge to incumbent GOP Gov. Butch Otter a contest that's taking place against a backdrop of an ongoing war for the soul of the Idaho Republican Party.
Otter is the so-called cowboy who's seeking a third term. His main opponent is Tea Party-backed state Sen. Russ Fulcher the "normal guy" whose campaign is grounded in his opposition to Otter's creation of a state-based health care exchange, among other things.
As a former member of Congress and as governor, Otter has amassed a solidly conservative record. But primary turnout is typically low in Idaho 27 percent or less in the past five primary elections which could provide an opening for Fulcher and the party's Tea Party wing.
Tuesday's marquee election is the Kentucky Senate primary and if McConnell wins comfortably, the news will come quickly because polls there close at 6 p.m. and 7 p.m. EDT (the state is divided between two time zones). Georgia is another state where the polls close early 7 p.m. EDT.
In addition to Arkansas (8:30 p.m. EDT) and Pennsylvania (8 p.m. EDT), there are two West Coast states voting Idaho and Oregon.
Oregon conducts its elections by mail; voted ballots must be received in a county elections office or designated drop site by 8 p.m. local time. Initial results are released at that time and are updated through the evening until all ballots have been counted.