Elmendorf previously served as an economist with the Treasury Department and the Federal Reserve. He was appointed to lead the CBO in 2009 after Peter Orszag, the previous director, was nominated to run the White House Office of Management and Budget. After that, in 2011, Elmendorf was confirmed for a four-year term after Republicans took over the House of Representatives.
Supporters of Elmendorf have said that the fact that he was reappointed by congressional Republicans shows that he isn't spiking the numbers to favor establishment Republicans or the Obama administration.
Over the past few months Republicans have renewed their focus on changing the way CBO scores budgets if they were to take control of the Senate and keep control of the House of Representatives. Dynamic scoring calculates budgets through a controversial view that tax cuts both create economic growth and counter lost revenue. Currently the CBO does not use dynamic scoring.
Both Rep. Paul Ryan (R-WI), the incoming chairman of the House Ways and Means Committee, and incoming Senate Majority Leader Mitch McConnell (R-KY) have argued in favor of dynamic scoring.