(CNN) A Democratic candidate challenging House Intelligence Committee chair Devin Nunes took in more than $1 million in the first quarter of 2018, a sign of Democrats' enthusiasm to oust the California congressman who has allied himself closely with President Donald Trump.

Andrew Janz, the Deputy District Attorney in Fresno County, is still considered a long shot in his bid to unseat Nunes. CNN currently rates the 22nd District as a "safe Republican" seat. But Nunes' role in running interference for Trump on the investigations into Russia's role in the 2016 election has made him a target for Democrats nationwide.

According to fundraising figures provided to CNN by the campaign, Janz has raised more than $1 million so far in 2018 with just three days left in the first quarter. The campaign received a huge influx in fundraising cash from donors across the country in the wake of Nunes role in releasing a controversial memo detailing concerns Republicans on the House Intelligence Committee had with the federal investigation into Russian interference in the 2016 election.

"We feel like he is the one person that is really standing in the way of the (FBI Special Counsel) Robert Mueller investigation," Janz told CNN. "We think people deserve to know what happened to our elections in 2016 and what is happening in 2018. And every day my opponent is out there trying to undermine federal law enforcement, the special prosecutors probe and really working for Trump instead of the American people."

Janz said that Nunes' focus on defending the Trump administration's role in the investigation, instead of focusing on issues important to California voters, is part of what is leading to the fundraising surge.

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