Republican Congressman Dana Rohrabacher has drawn a field of 15 challengers — including eight Democrats — but most dramatic was the last-minute entry of one-time ally and former county GOP Chairman Scott Baugh.

After a year of campaigning by a steadily swelling Democratic field, the filing period closed Friday evening, with observers pondering whether Baugh will endanger Democrats’ chances of advancing out of the top-two primary in the coastal Orange County’s 48th Congressional District. Because of the large Democratic field facing off against two established Republicans there is a chance of both Rohrabacher and Baugh making it to the November ballot.

Meanwhile, in Rep. Mimi Walters’ reelection bid, she is the only Republican candidate, making it likely she’ll face a Democrat in the general election. Four Democrats and an independent filed their candidacy papers by the deadline. Walters’ 45th Congressional District extends from Laguna Hills to Anaheim Hills.

Orange County’s four Republican-controlled congressional districts are all targeted by national Democrats hoping to take control of the House of Representatives, in part because Hillary Clinton prevailed over Donald Trump in each. The filing deadline for the seats of retiring Reps. Ed Royce, R-Fullerton, and Darrell Issa, R-Vista, have been extended to Wednesday, March 14, because of a provision for races where incumbents choose not to run.

Baugh, a longtime former friend of Rohrabacher’s, took out candidacy papers Wednesday and filed them shortly before the deadline. He has done no campaigning aside from 2016 fundraising for a possible bid which he subsequently put on hold. At the end of 2017, he had $540,000 in that account, according to federal filings.

“Three decades in Congress can change a person and unfortunately Dana has changed,” Baugh said in a statement emailed Friday evening about his decision to run. “He has lost focus on what’s important and does not seem to understand that the middle-class families in our district care more about their jobs, the economy and taxes than about Vladimir Putin, Julian Assange and marijuana.”

Rohrabacher has met with Assange and advocated friendlier relations with Russia as well as pushing for federal recognition of the more liberal marijuana laws in some states.

None of the eight Democrats hoping to take the 48th Congressional District has held elective office or Democratic Party posts — as a result, they began the race lacking name identification among voters. Baugh’s entry increases the possibility that Democrats will divide the left-leaning vote and leave the two established Republicans as the candidates who appear on the November ballot.

In California’s top-two primary system — dubbed by some a “jungle primary” — voters can cast a ballot for any candidate in the primary regardless of party affiliation. And the top two vote getters advance even if they’re from the same party.

“The nightmare scenario for Democrats is that two Republicans end up on the November ballot,” said Jack Pitney, a political science professor at Claremont McKenna College.

Democrats in the race are stem-cell biologist Hans Keirstead, former Nestle executive Michael Kotick, architect and business owner Laura Oatman, technology CEO Rachel Payne, businessman Harley Rouda, business owner Deanie Schaarsmith, attorney Omar Siddiqui and airline pilot Tony Zarkades.

The other Republican candidates to file are little-known business owners John Gabbard and Stelian Onufrei, technical writer Paul Martin and Shastina Sandman, who listed herself as “mompreneur/ CEO.” Filing as a Libertarian was business operations manager Brandon Reiser and making the deadline as an independent was Kevin Kensinger, vice president for an investment firm,.

In the challenge of Walters, Democrats are technology entrepreneur Brian Forde, former U.S. Senate aide Kia Hamadanchy, and UC Irvine law professors Dave Min and Katie Porter. Also running is retired UC Irvine business professor John Graham, an independent.