The Senate confirmed President Donald Trump's choice to head the Central Intelligence Agency Monday evening, while Trump's pick for secretary of state cleared his first hurdle en route to becoming America's top diplomat.

Kansas Rep. Mike Pompeo was confirmed as CIA Director by a 66-32 vote, the closest of three Senate votes on Trump appointments. Thirty Democrats, along with Sen. Bernie Sanders, I-Vt. and Sen. Rand Paul, R-Ky., opposed Pompeo, variously citing his positions on key issues like surveillance, torture and Russia's meddling in the 2016 election campaign.

The libertarian-leaning Paul told Fox News that he voted against Pompeo because of worries that Pompeo's "desire for security will trump his defense of liberty."

Pompeo, who was sworn in Monday evening by Vice President Mike Pence, will lead the CIA at a critical time for U.S. national security, when intelligence -- traditionally a nonpartisan issue -- has been thrust into the political arena. Trump has been critical of intelligence agencies' findings that Russia interfered in the 2016 campaign with the goal of electing him over Hillary Clinton.

Earlier Monday, the Senate Foreign Relations Committee voted along party lines to approve former ExxonMobil CEO Rex Tillerson as President Trump’s secretary of state, setting up a full Senate vote as early as next week.

Tillerson was assured of enough votes to avoid an embarrassing defeat in committee after Sen. Marco Rubio, R-Fla., decided to vote "yes" on Tillerson's nomination.

Rubio voted for Tillerson despite his concerns, and those of others on the committee, about Tillerson's past business ties with Russia.

“He has a proven record of running a large, complex company,” Rubio said before voting yes. “For me, this wasn’t simply a concern about Russia.”

Sen. Ben Cardin, D-Md. the top Democrat on the committee, voted against Tillerson’s nomination.

“I believe Mr. Tillerson’s demonstrated business orientation and his responses to questions during the confirmation hearing could compromise his ability as secretary of state to forcefully promote the values and ideals that have defined our country and our leading role in the world for more than 200 years,” he said before the vote.

Sens. John McCain, R-Ariz., and Lindsey Graham, R-S.C., had expressed concerns about Tillerson similar to those raised by Rubio. However, the senators said Sunday that they would support Tillerson in the final floor vote.

"Though we still have concerns about his past dealings with the Russian government and President Vladimir Putin, we believe that Mr. Tillerson can be an effective advocate for U.S. interests," they said in a joint statement.

Tillerson's nomination is expected to be approved by the full Senate since the Republicans have 52 senators in the chamber and 51 of them, a simple majority, are needed to vote “yes."

As CEO of ExxonMobil, Tillerson spoke out against U.S. sanctions levied on Moscow following its annexation of Ukraine's Crimean Peninsula in 2014. The penalties cost the energy giant hundreds of millions of dollars.

Fox News' Chad Pergram and The Associated Press contributed to this report.