The new conditions, coupled with the top-two primary, also have the potential to reduce Republican power in the state and in Washington. It's no wonder the party has been fighting to get the lines redrawn.
"Statewide, the big takeway is that the Democrats are going to gain a significant number of seats," said Jack Pitney, political science professor at Claremont McKenna College.
"The national implication is that the Democrats have a good outside chance to regain (seats) in the House. It's conceivable, it would be enough to put them over the top, and that's a hugely important development."
The impending departures of House Rep. David Dreier, R-San Dimas, and Rep. Jerry Lewis, R-Redlands, has opened the path for candidates who normally would have avoided challenging incumbents. Electoral redistricting appears to have had a major role in the Congressional retirements, said Pitney.
"The most immediate impact of redistricting was to hasten the leaving of Jerry Lewis and David Dreier, two of the most powerful members of the House with decades of seniority behind them," Pitney said.
"Both had been thinking about retiring anyway, but redistricting pushed them out the door. Jerry was placed in (Democratic Rep. Joe) Baca's district and David was placed in a heavily Democratic District. Both might have been able to find another district, but then they would have had to introduce themselves to large numbers of constituents, or face a fierce primary challenge. Neither wanted to do such a thing."
Also new this year is the open primary, where the top two vote earners move on to the general election regardless of party affiliation - paving the way for the entrance of independent primary candidates like former Assemblyman Anthony Adams, observers said.
Adams recently entered as a "no party preference" candidate for the newly drawn 8th Congressional District, a large area from the Nevada border in the east that includes Highland, Crestline, Twentynine Palms, Fort Irwin, and Baker. Whether he does well in this race may have statewide implications, said Alan Hoffenblum, editor and publisher of the California Target Book.
"The question is that if the independent candidates start doing well, it may be the beginning of a new third party developing in California," Hoffenblum said. "If you wanted to run as an independent, in the past, you needed thousands of signatures. This time around, all you need is to turn in 40 signatures, a filing fee, and write in `no party preference,' and you're on the ballot."
Doug Johnson, a Fellow of the Rose Institute of State and Local Politics at Claremont McKenna College, said it's likely both parties are analyzing what Adams' candidacy in the 8th means over the next few weeks.
"There's likely to be a lot more activity behind the scenes, trying to sort out whether all Republicans stay in the race, or the party narrows the field to make sure a Republican makes the runoffs," Johnson said of the race.
"It's going to be one of the funny dynamics of the top-two primary where we have a heavily Republican district. That makes it very attractive to a lot of Republicans, and they might split up the vote so much that no Republican makes the top two."
Lewis' decision to retire, has also opened up opportunity for half a dozen candidates to run for the new 31st Congressional District, comprised of Redlands, San Bernardino and Rancho Cucamonga. The district leans Democratic with 41 percent registered as Democrats and 36 percent registered as Republicans.
Here, state Sen. Bob Dutton, R-Rancho Cucamonga, faces Rep. Gary Miller, R-Brea, who now represents the Chino Valley in Congress. Several Democrats - Redlands Mayor Pete Aguilar, nonprofit founder Renea Wickman, educator Rita Ramirez-Dean and Justin Kim, a lawyer from Loma Linda - were attracted to the race.
"As these two men are duking it out for the Republican nomination, Pete Aguilar will be amassing his resources for the general election," said Renee Van Vechten, political science professor of the University of Redlands.
"He will be marshaling to battle either Miller or Dutton. If I had to guess, it's going to be a very tight race. Aguilar will get the Democratic vote and Republicans will be split between Dutton and Miller, so it would be very unlikely that it would be a two-way split between Republicans because Democrats have a slightly higher registration."
Reach Neil via email, call him at 909-483-9356, or find him on Twitter @InlandGov.