President Biden delivered his first address to Congress on Wednesday at a time when he and his party are emboldened by his largely popular agenda. The reviews were positive in a CNN poll and a CBS News poll conducted shortly after the speech. (The viewership skewed more Democratic than the electorate as a whole, though even accounting for that, people liked what they heard.)

But one prominent Democrat offered a somewhat harsh review, and his comments reinforced the biggest early liability for Biden as he pushes ambitious, trillion-dollar proposals: the border.

In a three-paragraph statement, freshman Sen. Mark Kelly (D-Ariz.) reserved the longest paragraph for what he thought Biden short-shrifted.

“While I share President Biden’s urgency in fixing our broken immigration system, what I didn’t hear tonight was a plan to address the immediate crisis at the border,” Kelly said, “and I will continue holding this administration accountable to deliver the resources and staffing necessary for a humane, orderly process as we work to improve border security, support local economies, and fix our immigration system.”

But just how much of a liability is this right now for Biden — both personally and politically?

Another CNN poll released earlier in the day provides some insight.

As with other polls, it showed immigration is one of Biden’s worst issues right now. While he received strong marks for his handling of the coronavirus pandemic (66 percent approval) and was in overall positive territory on most things, just 41 percent approved of his handling of immigration, while 53 percent disapproved.

That might actually undersell how bad an issue the border is for him right now.

A Washington Post-ABC News poll asked what people thought of Biden’s handling of the immigration situation at the U.S.-Mexico border, and Americans disapproved 53 percent to 37 percent. A Quinnipiac University poll earlier this month asked even more specifically about Biden’s handling of the issue. In that case, just 29 percent approved of Biden’s handling of it, while 55 percent disapproved. Only 58 percent of Democrats approved, and independents broke against Biden 64 percent to 22 percent.

It seems possible Biden’s marks in the first two polls were buoyed somewhat by support for his broader immigration proposals, but the more you focus the question on the border, the worse the numbers — at least according to the data we have.

Perhaps reinforcing Kelly’s point, the CNN poll also showed a vast majority of Americans, 78 percent, believe the situation on the border is a “crisis,” while 19 percent don’t. And 65 percent disapproved of how the U.S. government was treating border-crossers, compared with 29 percent who felt otherwise.

(The Post’s Nick Miroff wrote a must-read story this week looking at how the administration has struggled to deal with a surge in border crossings and overcrowded facilities.)

That last poll question is a little complicated. For example, people might not like what’s happening either because they don’t think Biden’s tough enough on the border or because they think his policies aren’t lenient enough. People who think border-crossers should be deported immediately or that they should simply be allowed into the country will both find something to dislike about the prevailing situation.

But broadly speaking, it shows how much of a problem this could be across the board for the administration. The question from there is how much of a priority this is for people and how much it will loom over the rest of Biden’s agenda.

For now, immigration is increasing as a priority in Americans’ minds — with a caveat.

While in January just 1 percent in Gallup polling said immigration was the country’s most important problem, that number has since risen to 14 percent, tied for second overall and sneaking up on the pandemic (20 percent).

That increase is driven overwhelmingly by Republicans, though. While just 5 percent of Democratic-leaning voters say immigration is the biggest problem, 25 percent of Republican leaners say it is — more than any other issue, including the pandemic.

That’s both a reflection of the saturation of coverage on this issue in conservative media, as well as the true nature of the crisis, which Miroff has been doing yeoman’s work in detailing.

But as Kelly’s statement shows, this is hardly a pittance, even in the minds of some Democrats. Biden did bring it up toward the end of the speech, but he spoke only briefly about the idea that passing his immigration proposal could help and said we should also address the root causes of why people from Latin America head north. Kelly, a border-state senator, clearly thought that was insufficient, to the point where he made it the focal point of his statement very shortly after the speech.

To the extent that Biden and his administration fail to deal with the crisis — which it has haltingly acknowledged is actually a crisis — it will both call into question his administration’s ability to implement massive government initiatives and resume giving his critics something to latch on to.

Biden in his speech, as he has before, suggested this is a somewhat-predictable consequence of how the Trump administration handled immigration, having gone with a hard-line approach rather than bothering with the causes of migration surges and how to deal with them more humanely.

But as with anything, you can blame your predecessor and the hand you were dealt only for so long. The administration has demonstrated a reluctance to play into the narrative that this is truly a crisis, and its allies have tried a little too hard to suggest that this is merely the normal course of things.

For Biden, the true problem here would be in allowing the situation to fester too long — especially when he has so many other ambitious things he wants to do, as his speech Wednesday demonstrated. It will be tempting for Biden allies to dismiss Kelly’s reaction to the speech as a consequence of him being a swing-state senator who is up for reelection in 2022. But he has otherwise been a reliable ally for Biden’s and the Democrats’ agenda. Perhaps he has some insight into this issue that the administration should take to heart.