In October 2011, Gill outraised every non-incumbant Republican in the country. (Neon Tommy)

9th District:

Republican Ricky Gill will battle Democratic Rep. Jerry McNerney for California’s newly-formed 9th Congressional District seat.

In October 2011 -- before Gill was even old enough to qualify constitutionally for office – the newcomer raised more money for his campaign than every other non-incumbent Republican in the country. The 25-year-old candidate finished law school at UC Berkeley in the spring before going on to address the Republican National Convention in the fall. His meteoric rise as a politician has caught the eye of GOP leaders, who see an opportunity in Gill and his fundraising prowess to unseat a Democratic congressman.

Despite all the hype about Gill, McNerney beat Gill in the primaries by about 9 percentage points. McNerney himself unseated a congressional incumbent in 2006 to gain a seat in the House of Representatives -- a rare feat considering that members of the house have almost always won in recent Californian congressional races. Since then, the self-proclaimed moderate Democrat has successfully fended off Republican challengers in 2008 and 2010. A newly-drawn district and a strong GOP challenger, however, could shake his odds.

10th District:

Democrat Jose Hernandez will challenge Republican and 19th Congressional District Rep. Jeff Denham for California’s 10th Congressional District.

Hernandez may have flown to space, but months ago a Sacramento law firm with ties to conservative lawmakers tried to prevent the candidate and former NASA employee from describing himself as an “astronaut” on the November ballot. As reported by the San Francisco Chronicle:

"Allowing a candidate out of nowhere to use the profession of 'astronaut' when he hasn't served in that profession recently is akin to allowing someone to use a title of 'sailor' when they no longer own or operate a ship," said Jennifer Kerns, a California Republican Party spokeswoman. 

A judge ruled against the firm and allowed Hernandez to use “astronaut/scientist/engineer” on the ballot.

Despite the victory, Hernandez faces an up-hill battle against a sitting Republican congressman in a congressional district that has said “no” to gay marriage and “yes” to Meg Whitman.

As for Denham, the Air Force veteran and former state senator succeeded Republican Rep. George Radanovich in 2010 after Radanovich called upon Denham to take his place. Denham won 49 percent of the vote during the primary, with Hernandez grabbing only 28 percent by comparison.

Neither candidate hails from the 10th district.

3rd District:

3rd district Republican Rep. Dan Lungren will square off against Democrat and physician Dr. Amerish “Ami” Bera for California’s newly-mapped 7th Congressional District seat.

Lungren, a former gubernatorial candidate, has crossed paths with Bera before -- in 2010, Lungren beat Bera in a race for the 3rd district seat by a margin of about 8 percent.

Two years have passed, the maps have been redrawn and now Democrats see the new district as an opportunity to paint a red seat blue.

Both have made the accusation that the other is some sort of doppelganger of a scarier politician from the opposing side. When Missouri Rep. Todd Akin said women rarely get pregnant from “legitimate rape,” Bera jumped to the occasion to compare Lungren with Akin, as both of them co-sponsored the same legislative bill to cut federal funds for abortions. Meanwhile, Lungren has ran ads calling Bera a “Pelosi clone.”

Reach Assistant News Editor Aaron Liu here. Follow him on Twitter.