Stop us if you've heard this before.

Senate Republicans walk into the new election cycle with a fantastic map on which to gain seats -- and potentially the majority. Compounding their opportunities are a series of early Democratic retirements in key states which appear to put the Democratic majority in even more jeopardy.

But lurking beneath the surface are two potentially troublesome developments for the GOP: 1) several of their primaries appear as though they may pit tea party-aligned insurgent candidates against candidates that the GOP establishment sees as more electable, and 2) the GOP talent pool in some of their top-targeted states is a little uncertain.

It happened in 2012. It's happening again in 2014.

In fact, the early months of the 2014 election cycle are shaping up to be remarkably similar to the first months of the 2012 cycle.

To wit:

In 2012, North Dakota Sen. Kent Conrad (D) announced his retirement early, giving the GOP what appeared to be a slam-dunk pickup. On Tuesday, Sen. Tim Johnson (D-S.D.) retired in the other Dakota, making open seats in South Dakota and West Virginia both likely pickups for the GOP at this early juncture.

In 2012, Virginia Sen. Jim Webb (D) retired early in a swing state, but Democrats were quickly able to recruit a top-tier candidate in Tim Kaine. This year, a similar scenario is playing out in Iowa, where Rep. Bruce Braley (D) has stepped in for retiring Sen. Tom Harkin (D).

In 2012, early retirements by Sens. Joe Lieberman (I-Conn.), Daniel Akaka (D-Hawaii) and Jeff Bingaman (D-N.M.) gave the GOP new opportunities in blue states. This year, the GOP could say the same about Michigan, where Sen. Carl Levin (D) is calling it quits, and to a lesser extent in New Jersey, where Sen. Frank Lautenberg (D) is retiring.

In 2012, Democrats' retirements outpaced GOP retirements early on, but the GOP did have a couple potential headaches with the retirement of Sen. Jon Kyl (R-Ariz.) and the resignation of Sen. John Ensign (R-Nev.). This year, they've got to deal with Sen. Saxby Chambliss's (R-Ga.) retirement in a soon-to-be swing state.

Given all that, the temptation for any political analyst is to focus on how good a chance the GOP has of gaining the six seats it needs to win back the majority.

And in fact, the landscape at this point is actually better for the GOP than it was two years ago, at least if you believe The Fix's Friday Line (and we do!). On our most recent line, nine of the 10 seats most likely to change control are held by Democrats. At this point in the 2012 cycle, that same top 10 list featured eight Democratic seats.

Of course, things turned out very differently than that by November 2012. While opportunity was certainly on the GOP's side early on, poor candidates and gaffes resulted in the party eventually losing two seats -- something that seemed almost unthinkable in March 2011.

The question is whether and how much the same things that brought the GOP down in 2012 bring them down again in 2014 -- namely, bad candidates and bruising primaries. And while most of the pieces have yet to fall into place, the stage is certainly set for a potential redux.

There are already a series of declared and potential candidates that the GOP establishment sees as less-than-desirable, including Reps. Paul Broun and Phil Gingrey in Georgia, Rep. Steve King in Iowa, Rep. Justin Amash in Michigan and former congressman Jeff Landry in Louisiana.

In addition, two candidates seen as early favorites -- former South Dakota governor Mike Rounds and West Virginia Rep. Shelley Moore Capito -- are already being targeted by GOP outside groups, despite having no declared opponents. The Club for Growth has made it known that it doesn't like Capito, and the Senate Conservatives Fund announced Tuesday that it will seek an alternative to Rounds.

In addition, groups like the Senate Conservatives Fund and the Club for Growth have recoiled at the creation of a new group led by Karl Rove that seeks to nominate more electable candidates.

Now, none if this is to say that the Republican Party is going to produce a bunch of Todd Akins and Richard Mourdocks again. But Akin and Mourdock weren't the GOP's only problems in 2012. The GOP also lost  because of candidates like then-Reps. Denny Rehberg (Mont.), Rick Berg (N.D.) and Connie Mack (Fla.) and former congressman Pete Hoekstra (Mich.), who all under-performed the top of the ticket by at least seven points.

This year, Republicans have either thin benches or unknown candidates in what are otherwise potential top targets in Michigan, Minnesota and Montana. And it's still unclear how strong GOP candidates will be in top-targeted Alaska, Arkansas and Louisiana. The GOP has struggled in the past to recruit quality candidates against Sens. Mark Pryor (D-Ark.), Max Baucus (D-Mont.) and Mary Landrieu (D-La.), in particular. (The GOP didn't even field a challenger against Pryor in 2008.)

The one major difference between 2012 and 2014, of course, is the size of the hill the GOP has to climb. While Republicans had to win either four seats or three seats and the presidency to control the Senate in 2012, they now must win six seats.

"D.C. Republicans seem overconfident once again, even though the math is much more difficult for them this cycle and their influence with the conservative base has waned," said Matt Canter, a spokesman for the Democratic Senatorial Campaign Committee.

While six seats is no small number, history suggests it's doable and there are certainly more than enough opportunities for Republicans to make that happen at this point. But there also is plenty that doesn't meet the eye standing in their way.

And Republicans are well aware of that.

"Yes, we'd rather be us than them," said Brad Dayspring, a spokesman for the National Republican Senatorial Committee, "but ... it's early, and it's incumbent upon us to capitalize on the opportunity."