Updated 9:38 p.m. | If Nevada’s lone Democratic House member decides to run for Senate, she could scramble the state’s Democratic field up and down the ballot.

Rep. Dina Titus is considering a bid to replace Senate Minority Leader Harry Reid, who made a surprise announcement Friday he is not seeking re-election.

“This is a decision I will make carefully after talking with family and close friends to ensure it is in the best interest of District One and the people of Nevada,” she said in a statement.

But almost as swiftly as his news went public, Reid endorsed former Attorney General Catherine Cortez Masto to replace him. He has often thrown his weight around to clear primary fields for his preferred candidate and prevent bruising Democratic primaries. But it is not yet clear if that will do anything to keep others from jumping in.

Reid acknowledged as much in a radio interview with KNPR Friday.

“Primary elections are not a disaster. … It’s a free country. If people want to run against her they should do that,” he said.

Titus has a history of bucking Reid’s preferences. In 2012, Titus, who had been unseated in the 4th District in 2010, decided to run in the 1st District. Reid backed her primary opponent, state Sen. Ruben Kihuen, behind the scenes. But Titus ultimately prevailed — Kihuen dropped out in February, effectively handing the seat to Titus.

In 2006, Reid quietly backed Jim Gibson over Titus in the Democratic primary for governor. Titus won the nomination, but lost the general election.

A Titus bid would shake up not just the Senate race, but also could scramble the House map.

Titus represents the geographically compact 1st District, which covers downtown Las Vegas. It is heavily Democratic — Obama won with 65 percent of the vote in 2012. Census data shows 40 percent of the district’s population is Hispanic.

That makes it an enticing prospect for ambitious Nevada Democrats. And that could pose problems for Democrats looking to recruit candidates to challenge Republicans in the harder to win 3rd and 4th Districts.

Kihuen announced Saturday he will challenge freshman Rep. Cresent Hardy, but Nevada Democrats said he could run for Titus’ seat, instead, should it open up. Same goes for former state assemblywoman Lucy Flores, the Democratic nominee for lieutenant governor last year, might opt to run in the 1st instead of her initial interest in the 4th.

Democrats still have a deep bench looking to challenge Hardy even if Kihuen and Flores are off the list. Hardy’s 4th District still leans Democratic.

But for the 3rd District, Titus’ old seat, the pickings will likely be slimmer. Obama and Republican nominee Mitt Romney split the vote in 2012 with 49 percent each. Republican Rep. Joe Heck now represents the 3rd, and has been a strong fundraiser, raising $2.5 million for the past election cycle.

Democrats see an advantage taking on Heck in a presidential year, but with openings in two neighboring districts that are far more favorable, recruiting a candidate to do so could be a harder sell.

Of course, that could change if Heck opts to run for Senate, something he has said on multiple occasions he will not do. Still, many Nevada operatives believe the Republican Senate field could grow like wildfire now that the winner will no longer have to face Reid.

“The Congressman will remain focused on serving Nevadans in the House,” Heck spokesman Greg Lemon told CQ Roll Call in an email on March 27.

Reid’s announcement, four days before the end of the first fundraising quarter, is well-timed to allow prospective candidates to get in quickly, but still gives them a full quarter to raise money and put on a show of fundraising force to kick off a campaign.

Titus would start with a slight fundraising edge over Masto. The congresswoman has $128,000 in her campaign war chest that she could use for a Senate bid. Masto, who has never raised money for a federal race, would be starting from scratch.

Former Rep. Steven Horsford, who lost the 4th District House seat last fall, said earlier this month he would not run for his old seat in 2016, but Democrats also mentioned his name as a possible Senate candidate. Reached by phone Friday, Horsford told CQ Roll Call he was in a meeting and could not comment at that time. Democrats said former secretary of state Ross Miller could also consider a run for Senate.

The Senate race is rated Tossup/Tilts Democratic by the Rothenberg & Gonzales Political Report/Roll Call.

Correction 9:30 a.m.

A previous version of this story misidentified Rep. Titus’ old district. It is the 3rd District.

Related:

Reid Plans Senate Exit: Not Running for Re-Election

Democrats Start With Narrow Advantage in Nevada

Reid, Durbin Endorse Schumer as Next Leader

With Horsford Out, Nevada Democrats Look Down Line

Republicans Fear 2010 Redux in Nevada Senate Race

Rothenberg & Gonzales 2016 Senate Race Ratings

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