A Senate recruitment victory for Democrats in Florida could, in turn, jeopardize the party’s quest for the House majority.

Rep. Patrick Murphy, a favorite of national Democrats for the state’s potentially open-seat Senate race, is announcing his statewide campaign Monday. That opens up the Treasure Coast-based House seat Murphy held for the past two cycles — one of just five Democrat-controlled House districts Mitt Romney carried in 2012.

Republicans have a voter registration advantage in the district, which Romney won by 4 points. It’s a seat Republicans say they never should have lost in the first place, and they are even more optimistic with it open.

“There is a strong Republican field growing down there,” said Rick Wilson, a Florida-based GOP consultant. “I don’t think Murphy’s luck the first time and no race the second time should be indicative of the competitiveness of the seat.”

Needing to pick up 30 seats for House control, if Democrats hold out any hope of winning the majority in the near future this is exactly the kind of district the party can’t afford to lose.

The last time Democrats netted at least 30 seats was in 2006, when an unpopular Republican president dragged the GOP down and Democrats won moderate and Republican-leaning districts. Democrats expect next year to be a far more favorable environment than the dismal 2014, with the presidential race driving turnout.

Murphy captured his House seat in 2012 by ousting incumbent Republican Allen West, a tea party firebrand and fount of provocative comments. West is now a Texas resident, he told CQ Roll Call during a recent visit to Capitol Hill, and cannot run for his old seat.

Since that election, Murphy has proved to be a politically astute incumbent. His strong fundraising coupled with his moderate voting record scared off top-tier GOP opponents in 2014.

After losing nine Senate seats in 2014 and with Republican Sen. Marco Rubio expected to vacate his seat to run for president, national Democrats are optimistic Murphy can win back the seat longtime Democratic Sen. Bob Graham retired from in 2004. The race is central to the party’s path back to the Senate majority.

But House Democrats could be hard-pressed to find a candidate with Murphy’s political chops in 2016. And this seat will be a top target for Republicans, who have few offensive opportunities left after significant gains in the past two midterm elections.

Florida Democrats insist they can hold the swing district, which covers the more urban area of northern Palm Beach County and more rural St. Lucie and Martin counties. Obama won it by 3 points in 2008, and potential 2016 nominee Hillary Rodham Clinton will likely run competitively.

“For the right Democrat, as Patrick Murphy has shown, it is a very, very winnable district,” said Eric Jotkoff, a Democratic consultant and former Obama spokesman in the state.

Democrats said they have a bench of candidates who appeal to the district’s voters and mentioned five possibilities:

• Palm Beach County Commissioner Melissa McKinlay, who was elected in 2014.
• State Senate Minority Whip Joseph Abruzzo, who has the moderate profile a Democrat would need to be successful. But he sounds more interested in running in the neighboring 21st District if Rep. Ted Deutch, D-Fla., vacates it.
• Palm Beach County State Attorney Dave Aronberg. A former Democratic state senator, Aronberg has bipartisan credentials. He worked for Attorney General Pam Bondi as a special prosecutor focusing on prescription-drug trafficking. He is well-known in the district..
• State Rep. Dave Kerner is an attorney and a former police officer who was first elected to the legislature in 2012.
• State Sen. Jeff Clemens helped McKinlay in her 2014 commissioner race and has said he would not run in a primary against her, according to the Palm Beach Post.

The Republicans mentioned as possible contenders in an open-seat race include:

• Reed Hartman, the past president of the Florida Farm Bureau’s State Young Farmers and Ranchers Leadership Group who hails from Martin County.
• State Rep. Pat Rooney Jr., the brother of GOP Rep. Tom Rooney, who represents the neighboring district.
• Businessman Gary Uber, who has never run for office. A source with knowledge of the discussions said Uber spoke with the NRCC about a bid.
• St. Lucie County Commissioner Tod Mowery, who was elected in 2010.
• Former State Rep. Carl Domino, the GOP nominee in 2014. A poor fundraiser, he limped out of a six-way primary in late August 2014 before Murphy trounced him with a stunning 60 percent of the vote — even outperforming GOP Gov. Rick Scott in Republican-leaning Marin County. Florida Republicans say they expect him to run again, but don’t sound thrilled by the prospect.

Assuming he captures the Democratic Senate nomination, Murphy will still be on the ballot in this district in 2016 and will almost certainly campaign there. That should help the eventual Democratic nominee for the House seat, and Murphy’s seal of approval could help bolster the candidate’s moderate credentials.

Of course, with Florida expected to host competitive presidential and Senate races, the eventual House nominees on both sides will be fighting for attention beneath a swarm of activity on the ground and airwaves and hoping for strength at the top of the ticket.

Related:

Murphy Announces Senate Bid

How Jeb Bush Affects the Florida Senate Race

How Republicans Could Risk a Senate Seat to Win the White House

Marco Rubio Names Potential Florida Senate Candidates

Are These 10 Vulnerable Members Lucky or Good?

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