Sanders posted his closest margin against Biden in Democratic primary polling since April, 23% to 29%.

Sanders outperforms Biden against Trump among voters ages 18-29, those who are not interested in politics and self-described independents.

Some Democrats are nervous that giving Vermont Sen. Bernie Sanders, a self-described socialist, the party’s presidential nomination would make it harder to achieve their ultimate goal of making President Donald Trump a one-term president.

Jim Messina, who managed former President Barack Obama’s 2012 re-election bid, said in a recent Politico interview that Trump would love to run against Sanders, noting that Republicans have already signaled they plan to hammer the socialism angle in the fall campaign.

But a new Morning Consult poll tracking the strength of the top Democratic contenders against Trump in hypothetical matchups found Sanders performs better than his rivals, including front-runner Joe Biden, with groups viewed as key to beating the unpopular incumbent.

Sanders leads Trump in the latest head-to-head polling 46 percent to 42 percent, picking up 2 percentage points on the incumbent Republican since the previous survey and statistically tied with Biden, who leads Trump 46 percent to 41 percent. The latest national survey, which was conducted Jan. 6-12 and polled between 8,218 and 8,386 registered voters, has a 1-point margin of error.