In the run-up to the midterm election, President Donald Trump and his allies in conservative media made exaggerated claims about an "invasion" of a roughly 3,500-person caravan of mainly-Honduran migrants headed for America’s southern border.

With the election in the rearview mirror, the migrant caravan has mostly faded from the headlines. But a new concern over illegal immigrants and the midterms got play on Lou Dobbs’ Tonight, with the host claiming many non-citizen voters cast ballots in the race.

"We are watching, you know, millions of illegal immigrants cross our borders," Dobbs said, "and many of them voting in the past election that's what, just a couple weeks ago."

Dobbs said illegal immigrants were having an "immense impact." He then went on to cite the potential consequences on the apportionment of congressional districts.

We found no basis for the Fox Business Network host’s claim about undocumented people voting in the midterms.

Allegations of undue influence over American elections have become fairly commonplace in the Trump era. Trump himself has repeatedly claimed the existence of massive voter fraud and election rigging, which we’ve debunked again and again and again and again and again and again and again.

In the case of the 2018 midterms, we’ve found no evidence to back up Dobbs’ claim that many illegal immigrants voted.

Fox News’ media contacts did not respond to our request for comment.

"There’s zero evidence of even dozens, let alone millions, of non citizens voting in this or any other election," said according to David Becker, the executive director of the Center for Election Innovation & Research, a non-profit focused on election integrity.

Dobbs’ claim that "we are watching millions of illegal immigrants cross our borders" needs context.

According to Department of Homeland Security figures, in fiscal year 2018 the U.S. Border Patrol caught 396,579 people crossing the southern border. A broader read of border crossings would also include department data on the number of foreign travelers to the United States who overstayed their visas, which was estimated at around 600,000 in fiscal year 2017.

As we’ve noted in a previous fact-check, there’s an oft-cited study among those claiming illegal immigrants have an outsized influence on U.S. elections. The study purports to show "14 percent of people who voted were noncitizens."

Many credible researchers have panned the study as methodologically unsound for using an opt-in Internet poll originally designed to survey citizens and not considering possible survey response error.

The federal government recently brought charges against 19 foreign nationals who voted in the 2016 election in North Carolina, where a total of more than 4.7 million votes were cast.

Experts said the Department of Justice under President George W. Bush, and Republican and Democratic election officials have investigated voter fraud extensively and found it is extremely rare. President Trump’s short-lived voter fraud commission couldn’t find any evidence of widespread fraud before being disbanded.

As for Dobbs’ claim, we rate it Pants on Fire.