The conservative movement has been able to stake its influence in terms of pushing top Republicans to move to the right, but they haven't always been able to translate that into electoral success. There are even a few House races where incumbent tea partiers face primary challenges from more mainstream Republicans. In the Senate, it's hard to see the most prominent tea party candidates even getting the Republican nomination, as conservative darlings like Christine O'Donnell and Joe Miller did in the past.
"Right now, it's not clear to me that we're going to have any of the Senate races where a high-profile incumbent gets bumped off by an insurgent radical tea party type," congressional scholar Norm Ornstein from the conservative American Enterprise Institute told TPM.
George Washington political scientist Sarah Binder agreed in an interview with TPM that there's not much territory for the tea party to gain in 2014.
"There's always a possibility that there are going to be pockets where the tea party can be more successful but there doesn't seem to be a groundswell of popular enthusiasm like there was in 2010 and somewhat in 2012," Binder said.
The most high-profile tea party challenge of the election cycle is the Republican primary for Senate Minority Leader Mitch McConnell's (R-KY) Senate seat. Bevin has managed to serve as enough of a nuisance to McConnell that the top Senate Republican has had to shape some of his campaign toward protecting his right flank instead of focusing all of his attacks on Secretary of State Alison Lundergan Grimes, the Democratic candidate in the race. But as late as January, Bevin himself admitted his candidacy is still a long shot.
"Statistically even now, it's crazy long odds and that by the latest polling among primary voters in the Republican ranks, I'm still behind," Bevin told Politico of his chances of defeating McConnell.
Bevin, at times, appeared like he could pose a real threat to McConnell, but now observers don't expect Bevin to win the race. Instead, Bevin has really just served to pressure McConnell to legislate more conservatively.
In South Carolina, Sen. Lindsey Graham (R-SC) is facing a handful of opponents in the Republican primary. So far though none of them have been able to move away from the pack and really serve as a danger to Graham, despite the senator's lackluster poll numbers. Graham also has a sizeable warchest that eclipses the funds of any of the candidates in the race.
Still, there are a few tea party candidates who have reason to hope. Ben Sasse, one of the top candidates in the Nebraska Senate race for retiring Sen. Mike Johanns' seat for example, has been embraced by conservative outside groups as well as Rep. Paul Ryan (R-WI), who isn't considered a core tea party lawmaker. There hasn't been a huge amount of polling on that race, but Sasse could win.
And in Mississippi, recent polling has shown state Sen. Chris McDaniel (R-MS) within striking distance of Sen. Thad Cochran (R-MS) -- despite reports that the tea partier attended a neo-Confederate event, blamed "hip-hop" for gun violence and even voted as a Democrat in 2003. McDaniel has also struggled to keep up in fundraising with Cochran and the incumbent Mississippi senator is still ramping up his re-election campaign.
What's less clear in the next few election cycles is what will happen to the tea party senators elected in 2010: Sens. Mike Lee (R-UT), Rand Paul (R-KY) and Ron Johnson (R-WI). Lee has suffered from plummeting poll numbers after the 2013 government shutdown. Paul has strongly hinted at a presidential run in 2016 so he might not run for re-election. Johnson, after a little inspection, could inspire some tea partier in Wisconsin to challenge him next time around.
There are still months to go and candidates are still introducing themselves, including some tea party favorites. Outside conservative groups don't sound worried, so far anyway. They argue that they can still help make a dent against incumbent Republicans, and even promise for 2014 primaries to see another "wave year."
"Both the number and degree of primary challenges are unprecedented. Whereas 2010 was a conservative wave year manifest in the general election, 2014 will be a wave year in the primaries," The Madison Project's Daniel Horowitz said in an email to TPM.
"Each group has its own strengths. FreedomWorks is good at mobilizing the grassroots while we're good at raising money for candidates," Senate Conservatives Fund Executive Director Matt Hoskins told TPM. "When conservatives unite like we've done in Mississippi and Kentucky, we can have a big impact."
Tom Borrelli, a senior fellow at FreedomWorks, told TPM that low approval approval numbers on President Barack Obama, Congress and really a "distrust of incumbent lawmakers" will create a groundswell of support for insurgent tea party candidates.
"I think it's going to be a year of significant change because most people don't get involved in politics until it really effects them and now we've had millions of people who 'mind your own business, take your kids to soccer practice' have received a letter letting them know their insurance has been canceled," Borrelli said. "So I think there's going to be a big shift."
And if there's any place where that shift seems likeliest, it could be for open seats on the horizon: In Oklahoma, for example, veteran tea party candidate Rep. Jim Bridenstine (R-OK) who won his seat from incumbent Rep. Jim Sullivan (R-OK) could jump into the race for outgoing Sen. Tom Coburn's (R-OK) seat. If he were to win that seat, tea partiers and outside groups would hail it as a major victory for the far right. The Senate Conservatives Fund is strongly encouraging Bridenstine, who has not decided whether to run or not, to jump into the race.
"Jim Bridenstine is one of the strongest conservatives in Congress, he's the ideal candidate to continue Dr. Coburn's fight against wasteful spending, and we should encourage him to run for the open seat," Hoskins wrote in a fundraising email on Thursday.
(Photo credit: Christopher O'Driscoll)