Don Blankenship, the controversial Republican candidate for Senate in West Virginia, responded on Thursday to sharp criticism from, by blaming "the establishment" for mounting attacks against his campaign.

"The establishment is doing everything they can to keepin office," Blankenship said in a statement to CNN , referring to the state's vulnerable Democratic Sen. Joe Manchin.

Blankenship, who trails significantly behind his primary opponents, West Virginia Republican Rep.and Attorney General Patrick Morrisey, is facing increasing pressure from Washington Republicans who fear that his run could hurt their plans to oust Manchin in November.

The GOP primary is Tuesday.

"No other Republican can beat Manchin without my full support, and neither Morrisey nor Jenkins is deserving of my support," Blankenship said in the statement. "West Virginians should be able to decide for themselves who we send to the U.S. Senate."

"I hate to lose. So I'm gonna go out on a limb here and ask the people of West Virginia to make a wise decision and reject Blankenship! No more fumbles like Alabama," Donald Jr. posted on Twitter on Thursday. "We need to win in November."

Trump Jr. responded to Blankenship by saying, "ha!"

"Now I’m establishment?" he tweeted. "No, I’m realistic & I know the first thing Manchin will do is run ads featuring the families of those 29 miners killed due to actions that sent you to prison. Can’t win the general... you should know that & if others in the GOP won’t say it, I will."

Ha, now I’m establishment? No, I’m realistic & I know the first thing Manchin will do is run ads featuring the families of those 29 miners killed due to actions that sent you to prison. Can’t win the general... you should know that & if others in the GOP won’t say it, I will. https://t.co/3dBmoVrMF1 — Donald Trump Jr. (@DonaldJTrumpJr) May 3, 2018

Blankenship is also under fire from a conservative group tied to Washington Republicans that has spent hundreds of thousands on attack ads against him.