Senate Majority Leader Mitch McConnell announced the leadership change on Monday afternoon, calling Rubio a "natural choice" for the position.
Senators have proposed a bill to rename the street of China's U.S. embassy after the coronavirus whistleblower.
The Florida senator said that denying the checks to people in mixed-status families is wrong and that he would intervene to find out what's happening.
Coronavirus has apparently exposed that some people need to keep spellcheck on.
The "Cuomo Prime Time" host said Americans should be angry that senators voted not to allow evidence in President Donald Trump's impeachment trial.
During the 2016 presidential primaries, Miller used Breitbart News to call Rubio a "pathological liar" and to label immigrants as "child sex offenders."
Miller said Breitbart's hit piece on Rubio was "phenomenal and important," and then-presidential candidate Donald Trump tweeted the story.
Republican strategist and CNN contributor Ana Navarro accused Rubio of being a "pretender" who has been reduced to a "caricature of his former self" after the senator wrote a tweet that appeared to defend President Donald Trump.
"The only way this actually ends is when we protect ourselves against those who would threaten us," Jack Keane said.
"We are voluntarily abdicating our role and it's the Russians, Iranians and others who are benefitting," Richard Haass warned.
"By abandoning the Kurds we have sent the most dangerous signal possible – America is an unreliable ally," the Republican senator from South Carolina argued.
Rubio told reporters that it is possible for the president to "do something that is wrong and not be an impeachable offense."
Florida Republican Senator Marco Rubio's comments came as President Donald Trump demanded all Bahamians fleeing the devastation of Hurricane Dorian have "totally proper documentation" before trying to come to the U.S.
"Hong Kongers are fighting for freedom, fighting for democracy, fighting for human rights," a pro-democracy activist said. "These are values that the United States stands for."
Finally, we agree that climate change exists. But now this, Senator Rubio?
"Hatred can be concealed by our acceptance of #WhiteNationalism and malice will be revealed in our cashing of NRA checks and failure to act," one Twitter user wrote.
Florida GOP Senator Marco Rubio threatened to publicly name Trump administration officials he accused of giving "fake leaks" to news media outlets.
Florida Senator mocked after backing man who referred to him as "Little Marco" in 2016.
"In no way should Huawei be used as a bargaining chip in trade negotiations," U.S. senators Mark Warner and Marco Rubio wrote in a letter, published today.
The legislation would force the government to seize financial assets and revoke or deny visas of individuals involved in expansionary Chinese policy.
The Florida senator says U.S. military action in Venezuela is "always" an option, citing the unstable presence of drug cartels, Marxist militant organizations and "hundreds" of Russian military advisers in the South American nation.
"Are we gonna be a hemisphere dominated by China, Russia and dictators?" GOP Representative Adam Kinzinger asked. "Or are we going to be a hemisphere dominated by freedom and democracy?"
Juan Guaidó, Venezuela's self-declared interim president, released a video from an air base near Caracas calling on Venezuelans to help topple President Nicolás Maduro.
Marco Rubio penned a withering critique of China's "zero-sum game" strategies, warning of its plans to replace the U.S. as the most powerful nation on earth.
"BIG NEWS for U.S. Auto Workers! The USMCA is already fixing the broken NAFTA deal," Trump wrote on Twitter.
The bipartisan bill pushes back against states that suspend the professional licenses of workers who can't pay back their student loans.
Senator Marco Rubio denied being behind the massive blackout in Venezuela, where President Nicolás Maduro vowed to defeat "American imperialism" trying to overthrow him.