Murphy says White House national security adviser should "stay out of politics"

Sen. Chris Murphy (D-Conn.) said on CNN's "State of the Union" Sunday that White House national security adviser Robert O'Brien should "stay out of politics."

Driving the news: O'Brien said on ABC News that it's "no surprise" Russia has attempted to interfere in favor of Sen. Bernie Sanders in the Democratic primary because Sanders "honeymooned in Moscow." Sanders said late last week that he was briefed about a month ago on Russia's attempts to help his campaign and that he completely condemns Putin's interference.

The big picture: A congressional briefing led by the Office of the Director of National Intelligence reportedly said that Russia had “developed a preference” for President Trump and was seeking to help his re-election campaign, in addition to Sanders' primary bid.

• O'Brien repeatedly said on the Sunday cable talk shows that he had not seen any intelligence to support this, despite Russia having interfered on Trump's behalf in 2016.
• Murphy countered on CNN: "What we know is that the Russians never stopped interfering in American politics. ... They are weighing in over and over again in support of right-wing causes, in support of Donald Trump's political agenda."
• "And of course it stands to reason that they want Donald Trump re-elected because he has been a gift to Russia," Murphy added.

Go deeper: Trump misrepresents 2020 Russia briefing as Democratic "misinformation"