Barely removed from the 2012 election, the 2014 chatter has already begun. In the Senate, much of it involves which incumbents might face primaries. For activists who've long opposed a senator despite belonging to the same party, the hope is that the scuttlebutt materializes into a strong challenge. But, the reality is that knocking a senator out of office in a primary is no easy feat. 

It's only happened eight times in the last 30 years. And two of the last five Senate incumbents who were felled in primaries still found a way to win the general election. 

Could Sen. Saxby Chambliss (R-Ga.) face a tough primary in 2014? (Yuri Gripas/Reuters)

The most recent example of a senator being dislodged in a primary came earlier this year, when Indiana Republican Sen. Richard Lugar lost to state Treasurer Richard Mourdock. Mourdock's feat was remarkable: Lugar became just the second senator since 1917 who served at least six terms to fall to an intra-party challenger. 

Conservative activists declared their upper chamber targets early in the 2012 cycle, but Lugar would be the only to go down. The political right in Utah was initially bullish about taking down Sen. Orrin Hatch (R-Utah) just two years after sending fellow Republican Robert Bennett packing. But Hatch prepared diligently for the expected opposition, and his challenger ultimately proved to be no match.

In Maine, where tea party groups put moderate Republican Olympia Snowe on notice early, no credible challengers stepped up. Snowe unexpectedly announced plans to retire earlier this year, but would likely have easily been reelected. 

Even after losing in primaries, a pair of senators remarkably managed to keep their jobs in recent years. Sen. Joseph Lieberman (I-Conn.) lost a Democratic primary in 2006, but won the general election as an independent  Sen. Lisa Murkowski (R-Alasaka) waged a successful write-in campaign after falling to conservative Joe Miller in 2010. Miller's general election campaign was nothing short of disastrous. 

History hasn't quieted the 2014 antagonists. Already, the head of the anti-tax Club for Growth has identified Sen. Lindsey Graham (R-S.C.) as a potential target, while the names of two potential challengers to Sen. Saxby Chambliss (R-Ga.) have surfaced in recent days. Meanwhile, the possibility that outgoing Montana Gov. Brian Scheweitzer (D) might try to wrest away the job of Sen. Max Baucus (D) hasn't gone away. 

Activists and conservative groups itching to force more Republican senators to join the ranks of Lugar and Bennett may face new complications in 2014. After a dismal 2012 cycle for Senate Republicans, the conservative super PAC American Crossroads and its affiliated issue-advocacy arm are mulling whether to pick sides in GOP primaries, with an eye on electability.  Meanwhile, the new leadership of the National Republican Senatorial Committee will be dispatching Sen.-elect Ted Cruz (R-Texas) to reach out to the some conservative groups including those with a track record of trying to oust GOP senators. Both moves could work against the grain of those who are dead set on sending certain senators into retirement. 

None of this is to say that Republican senators who have irked conservatives should ignore potential threats to their seats. A major reason Hatch still has a job and Lugar doesn't is that the former began carefully laying the groundwork for his reelection bid well in advance of Election Day and the latter stumbled in his campaign. Hatch also welcomed input from the tea party while Lugar all but shunned it. 

Unseating incumbents -- who enjoy a built-in name recognition advantage and often a fundraising edge -- is no small task. Though it looks as though the mission's odds, and occasional success stories, have not deterred those looking to make new attempts in two years.