Bernie Sanders sits atop a new national poll of the race for the 2020 Democratic presidential nomination, but it’s a close call with Joe Biden just behind.

In the CNN survey, 27% of registered voters who are Democrats or Democratic-leaning independents back Vermont Sen. Sanders, while 24% favor former Vice President Biden. CNN notes the margin between the two is within the poll’s margin of sampling error — so there is no clear leader in the poll.