An internal poll conducted for California Rep. Darrell Issa’s Democratic opponent shows Doug Applegate within three percentage points of the long-time Republican lawmaker.

The Strategies 360 poll released Monday by Applegate’s campaign, showed 45 percent saying they would vote for Issa, while 42 percent said they favored Applegate and 13 percent were undecided.

Strategies 360 said it polled 599 voters by landline and mobile phones from August 8 to 11. Issa’s 3-point lead is within the poll’s 4 percentage point margin of error.

An analysis of the numbers said Republican presidential nominee Donald Trump is a drag on Issa’s campaign — Issa has been a vocal supporter of the bombastic candidate, who has a high disapproval rating in the 49th District and trails Democratic standard-bearer Hillary Clinton by 5 points, 46 percent to 41 percent.

Republican Mitt Romney won the Southern California district by 6 points four years ago, though Barack Obama carried the district under its present boundaries by 2 points in 2008.

Applegate is a retired Marine Corps colonel in a district that encompasses Camp Pendleton and includes a number of military retirees.

[Darrell Issa Gets Viable Challenger]

“This poll shows that voters are tired of Congressman Issa continually putting party before country,” Applegate’s campaign manager Robert Dempsey said in a statement.

In the June primary, Applegate took 45 percent of the vote to Issa’s 51 percent. Issa won his last election with more than 60 percent of the vote. 

Issa’s campaign dismissed the poll, saying it “shows Issa is well positioned to win re-election this November.”

“Even in a poll conducted at the height of the Democrats’ post-convention bump, Congressman Issa has consistently stayed on top,” said Calvin Moore, communications director for Issa’s campaign. “The voters will send him back based on the strength of his proven record and his tireless work ethic in Congress.”