Laguna Beach Democrat Harley Rouda widened his lead over incumbent Rep. Dana Rohrabacher (R-Costa Mesa) to 3,602 votes Wednesday in the contest for the 48th Congressional District, leaving the longtime congressman fighting for his political life.

As of 5 p.m., Rouda had put more daylight between himself and Rohrabacher, with the latest results from Tuesday’s election showing him leading the race, 51% to 49%.

However, with an estimated 420,000 ballots still left to be tabulated countywide, according to the Orange County registrar of voters office, it may be some time before the dust officially settles in the closely watched race.

On Wednesday morning, Rouda told KABC-TV/7 that “part of you wishes it wasn’t this close,” but he added that “we’re cautiously optimistic we will be on top.”

“We need politicians and elected officials to fight for what you believe in but reach across the aisle, put country and community first, quit putting party first,” he told the station.

Representatives of Rouda’s and Rohrabacher’s campaigns could not be reached for additional comment Wednesday.

The 48th District runs from Seal Beach to Laguna Niguel and includes Huntington Beach, Costa Mesa, Fountain Valley, Newport Beach, Aliso Viejo and Laguna Beach. It also stretches into parts of Westminster and Garden Grove.

Throughout the campaign, Democrats expressed optimism that this could be their best chance yet to unseat Rohrabacher — who was first elected in 1988 — and in doing so tip over one domino in their quest to regain control of the U.S. House of Representatives.

Though the fate of the 48th was still not officially decided, Democrats had already seized enough seats to flip the chamber.

At his Election Night party Tuesday, Rohrabacher stood onstage at Skosh Monahan’s in Costa Mesa next to an old surfboard that read, “Give me liberty or give me surf,” and called his bid for reelection a race of “David against Goliath.”

A supporter shouted back, “Dana versus Goliath!”

Rohrabacher told supporters that Democrats had spent wildly to try to defeat him.

“We’ve had billionaires coming from outside,” he said. “We’ve taken on Goliath. We’ve taken on billionaires.”

Rouda, a lawyer and real estate businessman, qualified for the general election ballot by edging fellow Democrat Hans Keirstead by 125 votes in the June primary.

Rohrabacher and Rouda traded barbs in a debate last month, with Rohrabacher accusing Rouda of being soft on illegal immigration and Rouda claiming Rohrabacher “wants to deport everyone who is here undocumented.”

At that debate, Rouda also accused Rohrabacher of being soft on Russia, while Rohrabacher said, “We should cooperate with Russia now that it’s no longer our major threat, meaning the primary threat. They don’t meet our standards, but right now we have to deal with radical Islam and China.”

The Los Angeles Times contributed to this report.

RESULTS

Vote totals and percentages

Harley Rouda: 94,835 (51%)

Dana Rohrabacher (incumbent): 91,233 (49%)

Source: Orange County registrar of voters office, with all precincts reporting

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