Former vice president Joe Biden speaks at a campaign stop last week in Eldridge, Iowa. (Daniel Acker/Bloomberg News)
Opinion writer

New polling suggests that as of now the Democratic presidential primary race is former vice president Joe Biden’s to lose — and he might. In the general-election match-up, you really have to question why Republicans are sticking with President Trump.

On the Democratic primary, a new CBS battleground tracker poll tells us that in 18 early states (up through Super Tuesday), more than half of primary voters are considering supporting Biden (55 percent), followed by Sen. Elizabeth Warren (49 percent), Sen. Kamala D. Harris (45 percent), Sen. Bernie Sanders (43 percent) and South Bend, Ind., Mayor Pete Buttigieg, who still remains unknown to a good chunk of the primary electorate (32 percent). (Buttigieg runs more strongly in Iowa and New Hampshire, coming in fourth, presumably where he has spent the most time and among voters paying the most attention.)

When it comes to their first choice for nominee, Biden gets 31 percent, Warren 17 percent, Sanders 16 percent, Harris 10 percent and Buttigieg 8 percent.

Interestingly, in the Fox News national poll considering primary voters beyond the early states, Biden draws 32 percent, Sanders 13 percent and the trio of Buttigieg, Warren and Harris in a statistical tie in high single digits.

In short, the CBS poll is another poll in which the surging Warren has passed (if only by one point) Sanders. If Biden falters, the two female senators might benefit the most. To move up, Buttigieg needs to raise his profile (the debates will help), and perhaps most critically, expand his appeal among African American voters. He currently draws only 3 percent support from that critical voting group.

The good news for Democrats, once again, comes in general-election match-ups in the Fox News poll. Biden leads Trump by 10 points, Sanders leads by 9, Warren leads by 2 and Buttigieg and Harris lead by 1. Only Biden and Sanders for now are outside the margin of error.

Taking a step back, there are relatively few candidates currently in contention. In the RealClearPolitics average (with rounding), Biden is at 32 percent, Sanders all the way down to 16, Warren at 13, Buttigieg at 8 and Harris at 7. Only two other candidates are at or above 2 percent — Beto O’Rourke and Sen. Cory Booker. To sum up (again, for now):

  • Biden is leading and comfortably, in large part because he does extremely well with African Americans, and in the general-election match-up leads Trump by a mile (nearly 9 points in the RCP average).
  • Sanders is fading, in part because fresher faces with many of the same views are rising. (He beats Trump by a tad over 6 percent in the general face-off.)
  • Warren is surging but needs to improve with voters who aren’t as progressive as she is. She’ll also need to overcome doubts about her viability. (She’s generally ahead of Trump but within the margin of error.)
  • Harris has a good deal of upside since a large percentage of voters are considering her. However, so long as Biden draws so much of the African American vote, her ceiling is low. Should he falter, she is likely best positioned to win over those key voters.
  • Buttigieg’s name ID will improve with the debates, but he still faces the challenge of expanding his support to nonwhite and more moderate voters.

Remember: In the June and July debates, the 1 percent threshold will mean crowded stages and very little time to make an impression. Voters are not likely to react well to attacks, so don’t expect a lot of fireworks. By September’s debate, however, with a 2 percent threshold only five or six candidates are likely to be on stage. That’s when you might see more contentious moments, and when voters get a chance to compare and contrast among the most viable candidates, most likely appearing together on a single night.

If Trump continues directing his fire at Biden, we’ll know that his not-so-secret internal polling matches the public polling showing Trump getting slaughtered in a race against Biden. That makes Biden much more threatening to Trump than the prospect of impeachment.

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