text:  A just-released CBS News poll finds many Democrats have lost confidence in President Biden, especially after Thursday night's performance at the presidential debate. For months, voters have expressed doubts about whether President Joe Biden has that cognitive health to serve as president. And now those doubts have grown. After the debate, nearly three-quarters of the electorate, 72 percent of voters, don't think he has that cognitive health. And that includes four in ten in his own party. Jennifer DiPinto is the CBS News deputy director of elections and surveys.