Sen. Bernie Sanders (I-VT) has taken a narrow lead over Joe Biden (D), a Reuters/Ipsos national poll released Thursday revealed.

The post-debate poll, taken January 15-16, 2020, among 681 Democrats and independents, showed the socialist senator taking a narrow lead over Biden nationally with 20 percent support to the former vice president’s 19 percent. Sen. Elizabeth Warren (D-MA) came in seven points behind with 12 percent. No other candidate saw double-digit support.

Notably, billionaire Michael Bloomberg, who did not appear on Tuesday’s debate stage in Des Moines, Iowa, due to his decision to self-fund his campaign, thus making it impossible to reach the Democratic National Committee’s (DNC) contribution requirements, came in fourth place with nine percent support.

Former Mayor Pete Buttigieg (D) followed with six percent support.

Reuters reports:

Sanders and Bloomberg have increased their level of support in each of the last three Reuters/Ipsos polls starting in mid-December, while support for Biden, Warren and Buttigieg has remained flat.

The poll also shows that about one in five potential primary voters remain undecided. And among those who have picked, nearly two out of three say they are open to changing their minds.

As the poll’s results indicate, Sanders’ controversy with Warren, over alleged remarks regarding a woman’s capability of winning the presidency, did not result in a negative effect in the poll.