"I'm all in!" Feinstein tweeted. Feinstein's press secretary and communications director confirmed to TPM that Feinstein is running for re-election.
A fierce advocate for stricter gun laws and restrictions on semiautomatic weapons, Feinstein responded to the Las Vegas shooting - the deadliest mass shooting in recent US history - by calling for a ban on bump stocks, devices that allow some semiautomatic weapons to mimic an automatic weapon, which are illegal.
With Feinstein in, the question becomes whether anyone else challenges her, the likeliest being de León, who is termed out of the state Senate and has questioned her calls for patience with President Donald Trump.
Still, Feinstein is expected to have the support of most establishment Democrats already in office, and she already has the endorsement of her fellow California Democrat in the Senate.
Feinstein has been in her seat since 1992.
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There is still a chance for either side to top Group D , but that will depend on group leaders Serbia's result against Georgia . This would depend on who won their match tonight, as both Wales and the Republic could still come top of their group.
Feinstein has been showing all of the signs of another run in 2018, holding fundraisers and town hall meetings, and remaining an integral figure in Congress on gun-control and through her judiciary and intelligence committee posts. Chris Murphy, D-Conn., said that if Republicans were willing to pass a bill banning bump stock devices - like those used by the Las Vegas hotel sniper - he would support the legislation, even if it was not accompanied by any other restrictions of weapons purchases.
Feinstein is one of eight octogenarians in the US Senate. And most of the elected Democrats in the state are expected to back Feinstein. Sen.
"From my perspective, I think Feinstein probably wins".
Feinstein also has continuously expressed reservations about the so-called single-payer health care plan championed by many progressives, including Vermont Independent Sen.
"What Californians get from Dianne is someone who sticks to her principles and achieves results regardless of powerful opponents, from the assaults weapons ban to the Central Intelligence Agency torture report", Harris said. If the 83-year-old opts to retire, Mitt Romney, the 2012 GOP presidential candidate who now lives in Utah, is among those considering a potential campaign.