Is Maxine Waters, who defeated her Republican opponent in 2016 by over 50 points, actually vulnerable in 2018?

The California Congresswoman, who has been in Washington since 1991, tore into her Republican opponent on Twitter on Friday and today.

In a rare move for an incumbent in an seemingly safe seat — in a year the media is fantasizing about a Democratic takeover of Congress — Waters took aim at Omar Navarro in a series of acidic tweets.

Trump's campaign of crooks & liars against Congresswoman #MaxineWaters includes campaign consultant #RogerStone along w/ fundraiser/supporters #MichaelFlynn and #JoeArpaio — all in support of convicted crook Omar Navarro. Let's fight back! Donate today: https://t.co/Hbgb4K5MkV — Maxine Waters (@MaxineWaters) March 17, 2018

On Saturday, Waters attempted to raise money off the Trump backers supporting Navarro, calling them “Trump’s campaign of crooks & liars.”

On Friday, Waters attacked Navarro, calling him “Desperate, unstable, and (a) convicted criminal”, and called Michael Flynn “another indicted criminal”.

Desperate, unstable, and convicted criminal Omar Navarro stoops low in soliciting help from another indicted criminal in a campaign against #MaxineWaters – what a campaign! — Maxine Waters (@MaxineWaters) March 16, 2018

She wasn’t done.

“Indicted Michael Flynn who pleaded guilty about his conversations w/ Russians is in CA tonight campaigning for convicted Omar Navarro on probation for putting a tracking device on his wife’s car. Apparently the two will spend a lot of time together discussing their crimes,” she tweeted.

Indicted Michael Flynn who pleaded guilty about his conversations w/ Russians is in CA tonight campaigning for convicted Omar Navarro on probation for putting a tracking device on his wife's car. Apparently, the two will spend a lot of time together discussing their crimes. — Maxine Waters (@MaxineWaters) March 16, 2018

Can you believe Michael Flynn, an indicted (and guilty) liar and former National Security Advisor to Trump, has time to campaign for #MaxineWaters' opponent when he is supposed to be cooperating w/ Special Counsel Mueller in the #TrumpRussia investigation? — Maxine Waters (@MaxineWaters) March 16, 2018

A minute previously, Waters attacked Flynn, calling him “an indicted (and guilty) liar,” and alleged Flynn “is supposed to be cooperating w/ Special Counsel Mueller in the #TrumpRussia investigation”.

It is unusual for a “safe” incumbent to attack their opponent, especially by name.

Is Maxine Waters worried about her race?