By "big" I of course mean a competitive primary in a competitive state. (This is as opposed to something like Hawaii's Democratic Senate primary, which was a competitive primary in a non-competitive state.) That state is, of course, Alaska, where Republicans still haven't settled for sure who their challenger to incumbent Sen. Mark Begich will be.
According to polling, it's true, former Attorney General Daniel S. Sullivan has a comfortable lead--as he has in all polling conducted since the beginning of 2014. In the average he leads Lt. Gov. Mead Treadwell by 10 points, 37-27, and 2010 nominee Joe Miller by 19. Sullivan has also raised more twice the amount of money raised by Lt. Gov. Treadwell and Miller combined. While he's been outspent slightly by Lt. Gov. Treadwell, I've written before that the size of the campaign war chest is an indicator of the candidate's strength not so much because of the money he spends, but largely because it indicates broader (or at least deeper) support.
The one thing Lt. Gov. Treadwell (and, to a lesser extent, Miller) may have going for him is Sullivan's potential perception as an "outsider": Treadwell has lived in Alaska since 1978, while Sullivan lived up and down the East Coast most of his life until 2009, when Gov. Sarah Palin tapped him to become Attorney General. In aggregate it may be a minor concern, but for some citizens it may be a dealbreaker. (Personally, I felt that the fact that Tom MacArthur moved down from North Jersey just to run in the NJ-3 primary was a major turn-off.) And in Alaska, with a population less than that of the Columbia, South Carolina metropolitan area, the aggregate is not very large. (Sorry, Columbia, but you were the smallest metro area that was still bigger than Alaska. Nothing personal.)
Still, that takes a backseat to polling and fundraising, which suggest that Sullivan has all the advantages. One other thing that may work in Treadwell and Miller's favor is that polling in Alaska has historically been highly inconsistent (and I'm talking standard deviations of 10+ percentage points here). In 2008, polling in the last month before the election suggested anywhere from a 1-point victory for incumbent Sen. Ted Stevens to a 22-point blowout for eventual winner Mark Begich. And in 2010, the one poll, taken less than a month before the primary election, put Sen. Lisa Murkowski 32 points ahead of the eventual winner, Joe Miller. So it could be that polls are vastly overstating Sullivan's performance and/or vastly understating Treadwell's performance. But then again, it could just as easily be the other way around.
Finally, there's also the somewhat amusing possibility that Anchorage voters will mistake Sullivan for the mayor of Anchorage, Daniel A. Sullivan, and vote accordingly. (I would laugh if this actually happened.) With 42% of Alaska's population, Anchorage is where the votes are anyway. Humor aside, though, it's Sullivan's race to lose here. LIKELY SULLIVAN
