It's harder now for presidents to win Senate confirmation for their Cabinet picks, an Axios data analysis of votes for and against nominees found.

Why it matters: It's not just Neera Tanden. The trend is a product of growing polarization, rougher political discourse and slimming Senate majorities, experts say. It means some of the nation's most vital federal agencies go without a leader and the legislative authority that comes with one.

By the numbers: Not only are there more votes cast against presidential Cabinet nominees than in the past, but President Trump received no unanimous consent votes or voice votes for his nominees, which tend to indicate broad bipartisan support.

• President Obama had 19 such votes and President Bush had 23.

This year, the process is also taking longer. President Biden's nominees have been confirmed at a much slower pace than past presidents: There are now seven confirmed Cabinet members in addition to the director of national intelligence and U.N. ambassador.

• By Feb. 24, 2017, Trump had nine Cabinet nominees confirmed. At the same time in 2009, Obama had 12.