West Virginia Secretary of State Natalie Tennant (D) will launch a bid for Senate next week, sources confirm, setting up Democrats with their best remaining shot at retaining Sen. Jay RockefellerJohn (Jay) Davison RockefellerBottom Line World Health Day: It's time to fight preventable disease Lobbying World MORE's (D-W.Va.) seat.

Tennant will reportedly kick off her campaign next Tuesday, and then is expected to tour cities around the state.

She faces a difficult battle against top GOP recruit Rep. Shelley Moore CapitoShelley Wellons Moore CapitoAmerica is in desperate need of infrastructure investment: Senate highway bill a step in the right direction On The Money: Economy adds 164K jobs in July | Trump signs two-year budget deal, but border showdown looms | US, EU strike deal on beef exports Trump border fight throws curveball into shutdown prospects MORE (W.Va.), who is currently considered the frontrunner in the red-leaning state. The Senate seat is open in 2014 with the retirement of Sen. Jay Rockefeller (D). 

Though West Virginia hasn't sent a Republican to the Senate since 1956, Obama lost the state by about 25 percentage points in 2012, and Republicans see the seat as a prime pickup opportunity in their quest to retake the Senate.

Brook Hougesen, spokeswoman for the National Republican Senatorial Committee, immediately drew comparisons between Tennant and Senate Majority Leader Harry ReidHarry Mason Reid2020 Democrats fight to claim Obama's mantle on health care Reid says he wishes Franken would run for Senate again Panel: How Biden's gaffes could cost him against Trump MORE in a statement on her entrance into the race.

“Natalie Tennant is a cookie-cutter liberal more in the mold of Harry Reid (D-Nev.) than Joe ManchinJoseph (Joe) ManchinTrump vows to 'always uphold the Second Amendment' amid ongoing talks on gun laws White House eyes September action plan for gun proposals Trump phoned Democratic senator to talk gun control MORE (D-W.Va.) on issues like coal, energy, the EPA, ObamaCare, abortion and protecting the 2nd Amendment," she said.

She also suggested that Tennant is strategically useful for Republicans, because she could draw resources and energy from other candidates.

Strategically, Tennant is great for Republicans in that she's enough of a mirage to keep National Democrats and donors walking through the desert without offering the ability to ever drink," Hougesen said.

Republicans need to net six seats to regain the majority and have been counting on West Virginia, along with two other open seats where Democrats have been unable to front a strong candidate, as probable wins.

Tennant's entry into the race, however, gives Democrats a strong recruit. She was previously a businesswoman and broadcast journalist before winning the 2008 race for secretary of State with more than 60 percent of the vote.

She also ran unsuccessfully for the Democratic nomination in West Virginia's 2011 gubernatorial special election.

--This piece was updated at 4 p.m. to reflect comment from the NRSC.