Sure, Eric Cantor (above) lost. But the power of incumbency was still felt across the primary landscape. (AP Photo/J. Scott Applewhite, File)

Primary season is in the books. On Tuesday, five states held the final nominating contests ahead of the Nov. 4 midterms, which are now less than eight weeks away.

So what did we learn from the primaries and what do they tell us about the midterms -- and beyond? Below are the five biggest takeaways. (Think we're off-base or missed something? The comments section awaits your input!)

1. If Republicans don't win the Senate, it won't be because they didn't get the nominees they wanted. 

If the GOP doesn't gain the six seats it needs to control the upper chamber in 2015, it can't blame 2014 versions of Todd Akin, Sharron Angle or Richard Mourdock because they just aren't on the ballot this year. Simply, Republicans were much more successful in navigating Senate primaries than they have been in recent years. In Georgia, controversial Reps. Paul Broun and Phil Gingrey didn't even make the GOP runoff. In North Carolina, Thom Tillis easily outpaced conservative and irksome competition to his right, despite Democratic meddling. No Republican senator fell in a primary for the first time since 2008. Had some incumbents lost, states that are safely Republican could have been put in play. (See McDaniel, Chris.) But after being stung hard in 2010 and 2012 by flawed and controversial nominees who cost the party winnable seats, Republicans escaped the primaries in good shape. Part of the success was due to better -- and earlier -- preparation by incumbents. Part of it was the GOP groups Crossroads and the Chamber of Commerce playing in primaries on behalf of electable candidates. The result: The GOP got the nominees they wanted. Now the question is whether that crop of contenders can go out and win in the fall.

2. Being an incumbent is still powerful, even though people are fed up with Congress. 

When Rep. John Tierney (D-Mass.) was defeated by his primary challenger on Tuesday, he joined the ranks of just three other members of Congress who were ousted this year: Eric Cantor, Kerry Bentivolio and Ralph Hall. No senators were defeated. Polls have shown Americans expressing a deep, sometimes historic, dissatisfaction with Congress and even their own elected representatives. But that didn't result in a "throw the bums out" kind of primary season. Things may change when November rolls around, but the reality is that the platform afforded by incumbency remains a powerful one.

3. There are signs that turnout could be very, very low in November.

Voter turnout in statewide primaries was down 18 percent from 2010 in the first 25 states to vote this year, according a study by the Center for the Study of the American Electorate. If that trend continues in November, it could mean the drop-off from the presidential election year could be even more dramatic than anticipated, and the hardest core partisan voters would end up deciding pivotal contests. The side that does a better job firing up their base will be in strong shape come November.

4. The tea party will need to rethink its strategy in future elections. 

The primary season certainly wasn't devoid of tea party wins, but it was chock full is disappointing losses in the face of a much more prepared slate of moderate incumbents and challengers than in the past. National tea party groups poured big money into unseating Senate Minority Leader Mitch McConnell (R-Ky.) and Sen. Thad Cochran (R-Miss.). Both senators won -- and so did all of their colleagues, giving Republican senators a perfect primary season record for the first time since 2008. Those who seemed ripe for strong tea party challenges, like Sens. Lamar Alexander (R-Tenn.) and Lindsey Graham (R-S.C.), drew only gadfly competition. In the House, the anti-tax Club for Growth's crowd-sourced top target, Rep. Mike Simpson (R-Idaho), cruised to victory. The GOP establishment was much more aggressive than it was in 2012 and 2010. It prepared early, either scaring away top competition or hammering the challengers who did step up. It also sought to blacklist consultants who worked with insurgent challengers. The establishment found its groove. Now it's up to the tea party to respond and adapt in future elections.

5. The most important person in the battle for the Senate may be a candidate who didn't have to go through a primary.

We're talking about Greg Orman, the wild card independent candidate in Kansas who won't say which party he would caucus with if elected. Imagine a scenario in which Republicans gain exactly six seats, but Orman unseats Sen. Pat Roberts (R). It could happen. The independent would suddenly become the most sought after man in Washington as both parties would do everything in their power to woo him. The fact that the Democratic nominee dropped out without explanation after talks with Sen. Claire McCaskill (D-Mo.) suggests Democrats think there is at least a chance Orman, a former Democrat and Republican, would rejoin them. No one was talking about Kansas at the start of the 2014 cycle. But there's a chance everyone will be at its conclusion.