Rep. Darrell Issa, R-Calif., announced Wednesday he will not seek what would be his 10th term in Congress, making him the second California Republican this week, along with House Foreign Affairs Committee Chairman Ed Royce, to call it quits rather than face a possible Democratic wave in this year's midterms.

Issa's influence on Capitol Hill has waned recently, but for four years, he chaired the powerful House Oversight and Government Reform Committee, where he earned a reputation as a staunch critic of former President Obama and became a fixture on cable-news programs.

As chairman of the committee, Issa was a key player in GOP-led investigations looking at what Obama administration officials knew about controversial incidents including the 2012 terrorist attack on a U.S. Embassy in Benghazi , Libya, where four Americans including a U.S. Ambassador were killed, the IRS targeting of conservative groups and the "Fast and Furious" gun-trafficking scandal.

The ladder eventually led to the extraordinary 2012 contempt vote of then-Attorney General Eric Holder by the U.S. House. Holder refused to hand over internal Justice Department documents about a botched gun-sting operation in Arizona.

In a statement Wednesday, Issa said was "forever grateful to the people of San Diego, Orange and Riverside counties" and said it was an "honor" to serve them. He added:

"Together, we put an end to abusive congressional earmarks, strengthened the Violence Against Women Act, empowered better oversight of the executive branch, and cleared the course for better intellectual property protections to stop the piracy of American ingenuity."Throughout my service, I worked hard and never lost sight of the people our government is supposed to serve. Yet with the support of my family, I have decided that I will not seek re-election in California's 49th District."

Issa, 64, one of the wealthiest members of Congress, was first elected in 2000. As the Los Angeles Times points out, California's 49th district has changed since then, with growing Latino and Asian populations, and in the 2016 presidential election, Hillary Clinton defeated Donald Trump in Issa's district.

In his own 2016 race, Issa narrowly defeated a Democratic challenger — winning by only about 1,600 votes.

As NPR's Jessica Taylor reported, there are now 31 Republicans not seeking re-election in 2018. That number will likely grow, as Republicans in competitive districts have to make decisions about whether to run in an election year where their president has a historically low approval rating.

Democratic activist billionaire Tom Steyer this week pledged to put up $30 million dollars to help defeat Republicans in the midterms. Later Wednesday, Steyer's organization NextGen America tweeted out a statement praising Issa's decision:

"This week, we got our first wins with Darrell Issa and Ed Royce stepping down rather than face crushing defeat in November. Progressives are energized like never before — and today makes it more than obvious: Trump and the GOP are scared."

Issa was born in Cleveland, where he grew up in a working-class family. He dropped out of high school in 1970 to join the U.S. Army and earned the rank of captain.

In the 1970s, he had a couple of run-ins with the law, including an incident where he and his brother were arrested on suspicion of stealing a red Maserati sports car from a Cleveland showroom . According to an NPR report from 2012 , Issa said police mistook his identity and charges were dropped.

But by 1982, Issa created a car-alarm company called Directed Electronics, which he eventually moved from Cleveland to San Diego. Issa made a fortune from this business and he even provided the voice of the Viper car alarms that would warn people they were standing too close the vehicle: "Protected by Viper. Stand back."

According to the Center For Responsive Politics, which estimates politicians' wealth based on personal finance-disclosure information, Issa's estimated net worth was more than $323 million in 2016.

He used his substantial wealth not only to help finance his own campaigns through the years, but in 2003, he dropped $1.7 million to launch a signature-gathering effort to recall then-California Governor Gray Davis, a Democrat, according to the San Diego Union Tribune .

Issa had plans to run in the recall election against Davis, but eventually dropped out when actor-turned-politician Arnold Schwarzenegger entered the race.

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