Lisa Blunt Rochester

DOVER — Democratic congressional nominee Lisa Blunt Rochester said at a forum last month she supports making Delaware a sanctuary state, which would prohibit it from cooperating with the federal government in regard to detaining people illegally living in the United States.

Her Republican opponent is now seeking to make that an issue, turning up his criticism with less than a month to go until the general election.

In a video posted online Wednesday, Hans Reigle highlighted Ms. Blunt Rochester’s comments. The video, produced by the Reigle campaign, lasts about 90 seconds and argues greater steps are needed to prevent illegal immigration.

“It’s something that Delawareans feel strongly opposed to, I think, pretty much regardless of party, and it’s an important issue,” Mr. Reigle said Wednesday.

In a statement, Ms. Blunt Rochester offered details on her stance.

“Like most people, I believe our immigration system is broken and needs to be fixed. I’m committed to ensuring the security of our citizens as well as passing comprehensive immigration reform that is well monitored,” she said.

Hans Reigle

“However, there are already too many walls and barriers in the way of opportunity and we need to ensure that we remember who we are and what our values are. It is disappointing when politicians like Donald Trump and Hans Reigle try to win elections by capitalizing on fear instead of focusing on the real issues facing Delaware today. We must reject once and for all the notion that we have to enact hateful, racist and discriminatory immigration policies to keep our country safe.”

Mr. Reigle’s video cites the case of Kate Steinle, a San Francisco woman allegedly killed by an undocumented immigrant who had been released by authorities. The video summary also claims 12 people “are murdered by illegal immigrants” on a daily basis, an unsubstantiated statistic. The Washington Post called a similar statement by a U.S. representative “nonsense.”

Mr. Reigle said “not many” undocumented immigrants commit crimes but establishing a sanctuary state would greatly hinder police and prosecutors. He said the country needs to take greater steps to enforce existing laws and strengthen its borders.

Several of the United States’ major cities, such as New York, Chicago and San Francisco, have policies that limit immigration enforcement.

In 2015, Sen. Bryan Townsend, D-Newark, introduced legislation that would bar police from arresting or deporting anyone living in Delaware illegally solely on the basis of their immigration status.

He later withdrew the bill, which was spotlighted by Fox News in May, and said police in the state already follow many of the practices included in it.

Mr. Reigle and Ms. Blunt Rochester will have a chance to debate in person Wednesday at the University of Delaware, giving them both an opportunity to address the issue of immigration.