State Sen. Jim Tracy (R) raised $150,000 in the fourth quarter for his primary challenge to Rep. Scott DesJarlais (R-Tenn.), Tracy's campaign announced Monday.

Tracy now has $840,000 cash on hand and raised more than $1 million overall last year.

His campaign war chest dwarfs that of the embattled DesJarlais, who only had $170,000 in the bank at the end of September. He hasn’t yet released his fourth quarter fundraising numbers.

DesJarlais faced heavy criticism and calls to resign after filings documenting a messy divorce, which revealed the staunch anti-abortion social conservative urged his mistress to get an abortion, surfaced shortly before his 2012 reelection to Congress.

He’s considered one of Congress’s most vulnerable incumbents, and Tracy announced his challenge in January of last year. Tracy has already drawn the support of a number of Tennessee Republican leaders in his bid.

DesJarlais is facing a number of other contenders, but Tracy remains his strongest and best-funded competition.