But it's the races in the other four states that will influence U.S. politics on a national level.
Two-term incumbent Republican Sen. Lindsey Graham will likely defeat his six primary challengers and cruise to an easy win.
Graham is currently annihilating all opposition, which includes Columbia pastor Det Bowers, State Sen. Lee Bright, businessman Richard Cash, attorney Bill Connor, attorney Benjamin Dunn and businesswoman Nancy Mace, according to the latest polling data available from Real Clear Politics.
However, despite the fact that Graham was able to raise more cash than any of his challengers, and despite the fact that anti-GOP establishment sentiment never translated into real opposition, the Republican incumbent's six opponents create a slight chance he could fail to secure the votes required to avoid a runoff. If Graham can’t crack 50 percent of the vote in the primary, he will have to face off against the second-place finisher.
Incumbent Rep. Eric Cantor, R-Va., appears to have beaten back a strong Tea Party challenge fueled by opposition to his stance on immigration. But his challenger, economics and ethics professor Dave Brat, has definitely given the House majority leader a scare.
“Years ago he had a good conservative track record, but now he's veered off. He's not following what folks in his district want him to do and it's hurting the country,” Brat said in a recent ABC News interview.
Despite some sharp rhetoric and the Brat being backed by political pundits like author Ann Coulter and radio host Laura Ingraham, Cantor's victory is likely.
Elsewhere, in Virginia’s 8th District, former Democratic Virginia Lt. Gov. Don Beyer is expected to win his primary and go on to replace outgoing Democratic Rep. Jim Moran.
“Beyer started the race with the highest name recognition, has raised by far the most for the race and has brought in a number of big-name Democratic allies to campaign for him. If he wins, as expected, he's a lock in fall in this liberal suburban D.C. district,” the Hill reported.
Fun fact: Beyer has received endorsements from both David Axelrod and Oprah Winfrey.
The winner of the Democratic primary will go on to face Republican Micah Edmond and a handful of third-party candidates in the fall.
In the Republican primary, State Sen. Mark Hutchison, who's backed by Sandoval and much of the GOP establishment, faces former state Sen. Sue Lowden, who aligned with the Tea Party after losing the 2010 GOP Senate primary to challenge Reid.
The winner will face Democrat Lucy Flores.
The race's outcome could affect whether Sandoval — who is expected to win re-election — challenges Reid in 2016. If a Republican wins, he won't have to worry about turning the statehouse over to a Democrat.
Both Republicans and Democrats are facing off in primaries Tuesday to see who will replace Democratic Rep. Mike Michaud in the 2nd District.
“Emily Cain and Troy Jackson, both state senators, are facing off in the Democratic primary election. Cain, backed by Emily's List, is currently the frontrunner, having outraised Jackson by a large margin,” ABC News reported.
“In the GOP primary, former Maine State Treasurer Bruce Poliquin is facing former State Senator Kevin Raye. Raye is considered the frontrunner and is the more moderate candidate, which Poliquin has been hitting Raye on,” the report added.
President Obama carried the district with 53 percent of the vote in 2012.