Despite facing a federal investigation into questionable campaign spending, a new poll shows Republican Rep. Duncan Hunter holds a significant lead ahead of California’s 50th District June 5 primary.

The San Diego Union-Tribune and 10News poll showed 43 percent of respondents support Hunter. The closest competitor, former Obama administration staffer Ammar Campa-Najjar, had the support of 10 percent.

Hunter’s 2016 opponent, Democrat Patrick Malloy, trailed with 7 percent of respondents behind him, while El Cajon Mayor Bill Wells was 1 point behind him.

Jamul-Dulzura Union School District Board member and Navy SEAL veteran Josh Butner polled at 5 percent.

This comes despite Butner receiving campaign contributions from House Minority Whip Steny H. Hoyer, House Democratic Caucus Chairman Rep. Joseph Crowley and Rep. Seth Moulton.

California’s primary will be held on June 5, with the two candidates getting the most votes advancing to the general election regardless of party.

Hunter is under federal criminal investigation by the Justice Department for using campaign cash to pay for personal expenses.

The investigation has since dogged him, as he spent more money on legal fees than he received in contributions in 2017. But last fundraising quarter, he raised more money than he spent on legal fees.

The poll showed 58 percent said the investigation had a major or minor impact on how they will vote, but 72 percent of Hunter supporters said it had no impact on their decision.

The most important issue with voters polled was President Donald Trump’s job performance, with 29 percent of respondents saying it was the biggest factor in their vote.

Hunter was one of the first members of Congress to back Trump’s candidacy.

The poll, conducted by SurveyUSA, questioned 567 likely voters with phone calls between May 15 and May 20. It had a 5.1 percent margin of error.

Inside Elections with Nathan L. Gonzales rates the district Likely Republican.