West Virginia Rep. Shelley Moore Capito speaks to reporters at the Kanawha County Clerks Voter Registration Office in Charleston, W.Va., on May 13. (Tyler Evert/AP)

Correction: An earlier version misreported which conservative group ran ads in the race. It was the American Chemistry Council, not the 60 Plus Association.

The Senate Majority PAC will begin broadcasting television advertisements in West Virginia on Friday, expanding its campaign to help Democrats keep the majority into a state that conventional wisdom suggests is firmly in the Republican column.

The group will spend a little more than $200,000 on broadcast advertisements attacking Rep. Shelley Moore Capito (R) in the Beckley, Charleston and Clarksburg markets.

Capito leads Secretary of State Natalie Tennant (D) in private surveys, though there have been few reliable public polls. Neither Capito nor Tennant have begun broadcasting their own advertising. Only one group, the American Chemistry Council, has weighed in on Capito's behalf.

Senate Majority PAC, a super PAC run by former top Democratic Senatorial Campaign Committee officials, has spent $25.5 million on television advertising so far this year, giving Democrats cover from attack ads launched by outside conservative groups. They've spent most heavily in states like Arkansas, North Carolina, Louisiana and Alaska, states in which Democratic incumbents are fighting difficult reelection battles.

Through the end of June, the group had raised more than $29 million for the 2014 election cycle.

Republicans need six seats to win back control of the Senate, and their candidates are running well ahead of Democrats in Montana and South Dakota. In Iowa, Rep. Bruce Braley (D) is facing a surprisingly strong candidate in state Sen. Joni Ernst (R), who has begun to worry national Democrats hoping to keep retiring Sen. Tom Harkin's (D) seat; Senate Majority PAC began advertising against Ernst this week, too.

Returning to West Virginia, where Sen. Jay Rockefeller (D) is retiring and where President Obama is deeply unpopular, could represent Democratic efforts to expand the Senate playing field and save their majority.

Then again, one of the few groups less popular than President Obama is House Republicans.

Reid Wilson covers national politics and Congress for The Washington Post. He is the author of Read In, The Post’s morning tip sheet on politics.