Some swing voters are concerned President Biden isn't doing enough to discourage a surge of migration to the southern border — and they're worried about the buildup of child migrants in detention facilities.

Why it matters: For voters on the bubble between parties, the mounting immigration crisis — as well as rising fears about inflation — are presenting new litmus tests for the president, at a time when Biden hoped to be able to focus on the upsides to expanding COVID-19 vaccinations and stimulus.

These were among the biggest takeaways from our latest Engagious/Schlesinger swing-voter focus groups on governance in the Biden era.

• The two March 16 sessions included 12 women and men — from a mix of the most competitive swing states — who voted for Donald Trump in 2016 but Biden in 2020.

The big picture: Two months into the new administration, none of the swing voters are expressing buyer's remorse over Biden.

• But in addition to their concerns about undocumented immigration, most are concerned about unintended consequences of last week's passage of the $1.9 trillion economic stimulus.
• Eleven of 12 said they're concerned about inflation and the national debt. Only seven support the new child tax credit, and only one supported making it permanent.
• While focus groups are not statistically significant samples like polls, the responses show how some voters in crucial states are thinking and talking about national priorities and expectations for Biden.

Driving the news: While the Biden administration is turning away families attempting to cross the southern border without documentation, it has taken a stance of not turning back unaccompanied minors, citing humanitarian concerns.

• Since the policy shift from the Trump administration, there's been a major increase in unaccompanied children at the U.S.-Mexico border.
• That has overwhelmed border facilities and left children in worrisome conditions.

What they're saying: Several of the focus group participants say pleas from Biden and other top officials for migrants to stay home or wait until reforms are in place aren't enough.

• "I'm not sure that the countries that are sending their children up here are getting the message," said Connie B. from Michigan.
• Janet H. from Arizona said migrant children who arrive at the border "aren't our problem" and the U.S. "cannot be the world's savior."
• "I think he's not being firm enough, to say, 'Hey, people. It's not that we're against immigration, but... if you send your kids or you try to come here, we literally have nowhere to house you,'" said Kimberly M., a teacher from Arizona.
• On the flip side, Rob K. from Minnesota said Biden's policies are "no different" from Trump's and "they're still putting these kids literally in cages."

Yes, but: Many of these swing voters were no fans of Republicans' own visits to the border to try to showcase the surge.

• Frank R. from Florida, who is an immigrant, said Republicans are taking advantage of a tragic situation "to be able to get political gain." He said Biden "has bigger fish to fry" and that COVID-19 should remain his primary focus.
• David C. from Texas said Republicans are trying to win back political control.
• Kimberly M. and Connie B. suggested boosting foster parenting programs for migrant children.

The bottom line: "Swing voter support for Biden’s border policies is like sand falling through an hourglass," said Engagious president Rich Thau, who moderated the focus groups. "Right now there’s a reservoir of goodwill, but it’s depleting as time passes and impatience grows."