 Correspondent Bob Agnew reports. Senator Blumenthal told reporters he's deeply concerned about Biden's ability to win, but he was also quick to add that if he is a nominee, Biden will have his full support. He also called the reelection of Donald Trump an existential threat to the country. Behind closed doors, several Democrats expressed deep concerns on Tuesday about whether Biden can win, but no Democrat senator has publicly called for him to drop his reelection campaign. Bob Agnew reporting.