Story highlights Democratic senators grilled Donald Trump's choice to be education secretary in a hearing last week

Sen. Lamar Alexander explained his reasoning for not giving a second hearing in a letter Tuesday

(CNN) Sen. Lamar Alexander rejected a Democrat's request for a second hearing with Betsy DeVos on Monday, sparing Trump's pick for secretary of education from what would surely be a contentious hearing.

Alexander, the Republican chairman of the Senate Committee on Health, Education, Labor & Pensions, traded letters with Sen. Patty Murray, the ranking Democrat, who requested a second hearing for DeVos after all of her paperwork was approved by the Office of Government Ethics.

Even pro-Trump Republicans conceded that DeVos' delivered a lackluster performance in her confirmation hearing, where the Michigan Republican seemed unaware of certain federal education laws, argued that her decades in the leadership of her mother's foundation was a "clerical error" and appeared confused by certain teaching concepts when pushed by Democratic senators. Democrats also pushed DeVos about her desire to push for more access to charter, home and religious schools as Secretary of Education.

The hearing led many Democrats to believe that DeVos, a woman who straddles two immensely wealthy and politically active Republican families, could be their best chance to thwart a Trump cabinet nominee from getting approved.

"I have carefully considered the request and decided not to schedule a second hearing, and here is why: Already Mrs. DeVos has spent considerably more time answering questions of committee members than either of President Obama's education secretaries," Alexander wrote in his letter to Murray. "I do not know why our committee should treat a Republican nominee so differently than the nominee of a Democratic president."

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