Candidates in four key Orange County congressional races raised $29 million through March, more than double the amount raised in those same districts during the entire 2016 election season.

The fundraising reports filed by candidates in recent days offer some early clues into who could take the seats, and who might advance past the June 5 primary and make it to the general election in November. All four seats are held by Republicans and are targeted by national Democrats in an effort to take control of the House of Representatives.

The reports also hint at how competitive the GOP-held seats have become in a one-time Republican stronghold, showing action on all points of the political spectrum.

Baugh rivals Rohrabacher in 48th

Over previous election cycles Scott Baugh, the former state assemblyman and Orange County GOP Chair, amassed enough money to mount a strong challenge to longtime incumbent GOP Rep. Dana Rohrabacher. The new reports show he also has managed to keep pace in fundraising this year.

In the first-quarter of 2018, both opponents raised north of $300,000 in individual contributions, with Baugh raising that amount since mid-March, when he entered the race.

Baugh has been eyeing Rohrabacher’s seat for a while – raising around $500,000 in early 2016 – so the two men also have similar amounts of cash-on-hand, with $901,000 in the bank for the incumbent and $745,000 for the challenger. That means the former friends have enough money to wage public attacks against each other.

Baugh’s fundraising success also worries Democrats because it could signal a split in Republican support. If Baugh can win over enough of Rohrabacher’s GOP base, and if that base remains loyal to the party, the state’s top-two primary system could make it possible for two GOP candidates to advance to November even if more primary votes, overall, are cast for Democrats.

To prevent that, the top Democrats in the race – stem-cell biologist Hans Keirstead, businessman Harley Rouda, and trial attorney Omar Siddiqui – have raised, spent, and loaned themselves sizable sums. Keirstead, the top fundraising Democrat in the 48th, has brought in $826,000 this cycle in individual contributions, while Rouda trails with $634,000 and Siddiqui has $169,000.

All three Democrats also have loaned themselves substantial (Keirstead, $425,000; Rouda, $1.1 million; Siddiqui, $750,000) amounts, giving each candidate enough money to finance a flood of ads between now and June.

Republicans playing catch-up

Democrats in two districts (CA 39 and CA 49) benefited from a substantial head-start in fundraising. Many Republicans didn’t decide to run until January, when incumbent GOP Reps. Ed Royce and Darrell Issa announced their retirements. That jump start, coupled with at least some anti-Trump energy, allowed top Democrats in the four competitive contests to collectively raise $21.6 million – nearly three times the $7.5 million raised by the GOP’s top candidates.

Republicans are fighting to catch-up.

In the race to replace Royce, the three GOP frontrunners – former state legislators Young Kim and Bob Huff, and Orange County Supervisor Shawn Nelson – out-raised each of the contest’s Democrats in 2018’s first quarter; Kim, $607,000; Nelson, $397,000, and Huff, $312,000.

But some Democrats in the race have given and loaned their campaigns enough money to make their lead virtually insurmountable, even overshadowing other top-fundraising Democrats. And because of partisan voting patterns, the disparity between political parties matters less than variations within them. Republican and Democrat candidates primarily are competing against others from their own party to advance to the General Election ballot in November.

The big spenders so far are lottery-winner and philanthropist Gil Cisneros and former insurance executive Andy Thorburn, who have spent nearly $1.5 million and $1.8 million, respectively. Cisneros loaned his campaign $2 million, while Thorburn gave and loaned his campaign $2.3 million. But among top Democrats in the race, the two men have raised the least from outside sources.

Instead, pediatrician Mai Khan Tran raised the most of any Democratic candidates in the contest, totaling $686,000 in outside money. And Sam Jammal, an attorney who brought in a total of $430,000 in the campaign cycle, raised the second most from outside sources in 2018 of any Democrat in the race. For both candidates, the fundraising could signal grassroots support. Nevertheless, Jammal’s total is much smaller than other Democratic candidates – only one-sixth of the amount obtained by the Cisneros or Thorburn campaigns.

The top 2018 fundraiser among Democrats vying to replace Royce was Cisneros, who brought in nearly $185,000 in outside money in January through March.

Some frontrunners spending less

Republican Rocky Chavez and Democrat Doug Applegate were the top polling candidates in a recently released SurveyUSA poll conducted for 10News and The San Diego Union-Tribune, receiving 16 percent and 12 percent respectively. But both candidates, competing to replace Issa in the 49th, have spent substantially less than their opponents.

So far, Chavez has raised $204,000 and spent only $19,000, by far the least of any top GOP candidate in the 49th District.

Likewise, Applegate – who nearly unseated Issa in 2016 in the nation’s closest House race – brought in $133,858 in the first quarter of 2018 and ended with $235,000 on hand, the least of the four Democrats in the contest.

Chavez has polled well despite being outspent by other Republicans, including San Juan Capistrano Councilman Brian Maryott, who has spent $362,000, Board of Equalization member, former Assemblywoman Diane Harkey, who spent $133,000, and San Diego County Supervisor Kristin Gaspar, who spent $76,000.

On the other hand, Applegate has fallen in the polls during his period of low spending, dropping six percentage points from a previous SurveyUSA poll conducted for the two San Diego news organizations.

He has yielded that support to real estate investor Paul Kerr, attorney Mike Levin, and former nonprofit CEO Sara Jacobs – all of whom are hovering between 7 and 9 percent in the poll. Those candidates have spent more than Applegate and all still have lots of cash on hand: Kerr spent $1.1 million in the first portion of 2018 and ended with $345,000; Jacobs spent $443,000 and has $1.1 million in her account; and Levin spent $297,000 and has $515,000 cash on hand.

Two of Applegate’s opponents also are largely self funding their campaigns. Records show Jacobs has given herself $1.1 million, while Kerr has given himself $1.6 million. Meanwhile, Levin and Applegate have raised nearly all their money from outside sources.

The race to face Mimi Walters

All four Democrats taking on GOP Rep. Mimi Walters in CA 45 have raised enough from individual contributors to be competitive to reach the ballot in November.

Technology entrepreneur Brian Forde has taken in $1.2 million, UC Irvine law professors Katie Porter raised $1 million, another UC Irvine law professor David Min accumulated nearly $900,000 and former U.S. Senate aide Kia Hamadanchy raised $573,000.

Walters, meanwhile, has $1.7 million on hand after spending $280,000 in the first quarter of 2018.

CORRECTION: A previous version of this story misstated which 39th Congressional District candidate raised the most outside money in the first quarter of 2018. It was Gil Cisneros.