Story highlights Rep. Darrell Issa nearly lost his seat in 2016

His decision not to run comes amid a wave of retirement announcements

Washington (CNN) California Republican Rep. Darrell Issa will retire at the end of his term, he announced Wednesday.

Issa, one of the wealthiest members of Congress and among the best-known due to his reputation as a conservative attack dog, is bowing out of what would have been one of the nation's most hotly contested congressional races.

He told reporters Wednesday as he left the House floor that "it was time," but that he plans to stay involved in politics and spend his own money helping Republicans.

"I'm going to be 65 and happily looking forward to doing other things," Issa said. "I intend on staying very involved in both contributing my time and money because I believe in the issues I came here 18 years ago so there's nothing changing."

He nearly lost his seat in 2016, besting Democrat Douglas Applegate -- among the four Democrats running this year -- by less than a percentage point. It's among seven Republican-held districts in California that Hillary Clinton won that year, carrying Issa's by 8 percentage points.

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