Former Vice President Joe Biden’s respective leads over Sens. Kamala Harris of California, Elizabeth Warren of Massachusetts shrink by 9 and 6 percentage points in poll of Democratic primary electorate’s most likely voters.

Sens. Kamala Harris of California and Elizabeth Warren of Massachusetts have risen up the ranks of contenders for the Democratic presidential primary in recent months, closing the gap between the field and its current leader, former Vice President Joe Biden.

New Morning Consult polling showing preferences among the primary electorate’s most likely voters suggests that gap may be even smaller than it appears.

Biden holds respective 17- and 18-point leads over Harris and Warren in the latest survey of 16,599 Democratic primary voters, conducted July 1-7. But that advantage shrinks to 8 points over Harris and 12 points over Warren among the 4,604 voters who are most likely to vote: those who said they’re absolutely certain to vote in 2020, have voted in previous elections and are extremely interested in politics and public affairs. Both samples have 1-point margins of error.

Democratic strategist Adrienne Elrod, who served as director of strategic communications for Hillary Clinton’s 2016 campaign, said the polling shows Biden’s support to be soft — particularly among the most motivated voters.