For nearly 10 minutes on Monday, the Republican congressman from California's central valley stood at the door of a building that he believed to be housing unaccompanied migrant children, some of whom had been separated at the border.

He kept knocking, but no one answered.

"They've been told by (the Office of Refugees and Resettlement) not to answer the door or talk to you for right now," a security guard outside the premises told Denham.

"They knew I was coming a week ago," Denham fired back.

Denham is the latest member to attempt to enter a facility housing unaccompanied minors. While many members have toured facilities, the rules surrounding such tours are heavily enforced, including guidance from the Department of Health and Human Services that lawmakers should request such tours two weeks in advance. Denham said he requested a tour more than a week prior.

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As he fights for his political life back home, Denham's become a high-profile member in recent months in Washington, the leader of a rarely used procedural motion known as a discharge petition, which would have bypassed Republican leaders and forced votes on four separate immigration bills. Denham eventually abandoned the petition in favor of working with House leaders to craft a Republican-only bill. Monday's visit came less than a week after the vulnerable House moderate watched as his colleagues overwhelmingly reject an immigration bill he spent weeks negotiating, a bill that had intermittent support from the White House and earned just 121 votes.

His role in the immigration debate isn't lost on his constituents back home.

Earlier that morning, more than an hour east of the immigration facility, Denham stood at the front of the Waterford Community Baptist Church trying to answer for his role in the latest immigration debate back in Congress. The issue isn't hypothetical here. California's 10th Congressional District is heavily agricultural and more than 40% Hispanic, a place where the local church doubles as a tutoring center where adults can come to learn English as a second language at night and a place where local farmers will tell you they've struggled to find enough workers in recent years to harvest their walnut and peach crops.

"I'm not happy that you're involved with the discharge petition," one woman states at the beginning of a question and answer session in Waterford, California. "I'm not at all happy about that."

"The only thing I know is that the United States cannot take care of everyone that wants to come. We have people of our own here. And I know this is a wonderful country to come to, but we do also have to think about we can't overload it," said Myrna Stine, a local resident who says she'll still vote for Denham.

Denham tries to defuse the situation when he's on the road. It's a balance in a district that Hillary Clinton won by 3 percentage points in 2016.

Not everyone is critical. At a local taqueria in Hughson, in the back of the restaurant by the bar, Marie Assali tells Denham, "I feel bad for you," noting that she watches the news and sees all the coverage he's getting in Washington as he tried to pull the immigration bill together.

"I'm really happy with what's he's trying to do with immigration," Assali told CNN. She and her husband work in agriculture and are very familiar with the limitations of the current system. "I don't understand all of the different aspects. I just want the people who want to be in America, that want to work, that are already here with their families, I think they should have a chance to stay."

Greg Bennett tells CNN he thinks Denham is at least "going in the right direction."

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"At least he has the mind to know that we have a problem and is willing to fix it," Bennett says.

"This immigration debate's been tough," Denham said at the conclusion of his meet and greet in Waterford. "It's been difficult. It's pushed me to do things that I never thought I would do before, but sitting back and taking a backseat and doing nothing is not an option."

Denham's Democratic opponent is 31-year-old former venture capitalist and junior college teacher Josh Harder, who is taking aim at Denham's latest role in the immigration debate. Harder has argued that Denham gave up on real immigration reform and instead opted for a watered-down, Republican-only bill that died in the House anyway. It's part of Harder's push and the broader narrative that Harder believes Denham has abandoned the district on immigration, health care and tax reform.

"Every single time push comes to shove, he abandons his constituents and votes his party line," Harder told CNN in an interview Monday. "This district is sick and tired of a trail of broken promises with nothing to back it up."

Denham tells constituents when asked that the immigration issue "has to" be solved this year, but there's little reality it could happen. House leaders were already skittish about debating immigration just months ahead of a midterm election. With their backs against the wall because of the discharge petition, they engaged. But now, the only immigration debate that could come back to the floor is a bill that would narrowly address family separations and perhaps a bill to deal with a guest worker program. After Denham's bill and a more conservative proposal have both fallen short, there's little optimism another comprehensive bill would gain traction this year in the fractured GOP conference.

On the front steps of the immigration facility in the suburbs of San Francisco, Denham vows just like he has with comprehensive immigration, that he'll try again. But the odds are stacked against him. For nearly an hour, Denham tried to call contacts he had, but no one inside the facility would answer. Instead, a maintenance worker on the property came out and handed Denham a piece of paper with contacts he already had.

Denham left not knowing key pieces of information about the facility. How many children it housed, how many children inside had been separated from their parents as a result of the zero-tolerance practice on the border or how those children were being cared for.

"We don't know and that's part of the frustration," Denham said. "If they have a good accounting of exactly where these unaccompanied minors are, if they know exactly how many kids have been taken away from their parents and how they plan to reunite them, those are the answers that we should see. We should not only be able to see the conditions that these kids have, where they are sleeping, whether or not they are getting an education while they are here, whether or not they are eating while they are here, we should know all of these issues up front."

Denham vowed to come back.

"I'll go back to the district tonight, but obviously this issue isn't going away," Denham said.