Amid what could be the tea party’s last hope for victory this spring, Mississippi’s neck-and-neck Republican Senate race Tuesday between incumbent Sen. Thad Cochran and tea party-backed state Sen. Chris McDaniel, has the potential to irrevocably impact the anti-establishment group, which has caused a rift in the Republican Party.

Yet, as the GOP tries to reclaim a majority in the Senate this November, the retirement of Democratic senators in Iowa and in South Dakota, also holding primaries Tuesday, could be good news for Republicans, who are expected to nominate strong candidates. In the general election, these seats could switch from Democratic to Republican.