Booker snags first Senate endorsement
© Greg Nash
Sen. Bob Menendez (D-N.J.) endorsed fellow New Jersey Sen. Cory BookerCory Anthony BookerSenate Democrats demand answers on migrant child trafficking during pandemic Senate Democrats push to include free phone calls for incarcerated people in next relief package Ex-USAID employee apologizes, denies sending explosive tweets MORE's (D) presidential bid on Friday, making him the first senator to endorse a colleague in the party's crowded 2020 race. 

"I can't think of anyone better to represent and unite the American people. Cory makes a great friend, and will make an even greater president. I can't wait to support you on this journey—I'm all in!" Menendez said in a tweet on Friday.  
Booker made his long-anticipated announcement that he was running for the party's 2020 nomination Friday morning, the first day of Black History Month.
Menendez's endorsement of Booker isn't a surprise. The two New Jersey lawmakers have been close partners in Congress. Booker also testified on Menendez's behalf during his corruption trial in 2017. 
Though Menendez is the first senator to endorse a fellow senator during the 2020 cycle, some lawmakers have thrown their support behind other candidates. Sen. Dianne FeinsteinDianne Emiel FeinsteinSenate Democrats demand answers on migrant child trafficking during pandemic Yates spars with GOP at testy hearing Democrats want Biden to debate Trump despite risks MORE (D-Calif.) said last month that she would back former Vice President Joe BidenJoe BidenBiden says Trump executive order is 'a reckless war on Social Security' Trump got into testy exchange with top GOP donor Adelson: report Blumenthal calls for declassification of materials detailing Russian threat to US elections MORE if he ran. Feinstein's California counterpart, Sen. Kamala HarrisKamala Devi HarrisBiden campaign says no VP pick yet after bike trail quip Hillary Clinton roasts NYT's Maureen Dowd over column Biden edges closer to VP pick: Here's who's up and who's down MORE (D-Calif.), is also running for president and won Rep. Ted LieuTed W. LieuGOP official says Elizabeth Warren 'endorses voter fraud' after joke about Bailey voting for Biden Milley confirms soldiers deployed to DC amid unrest were given bayonets Trump campaign touts 4M online viewers for Tulsa rally MORE's (D-Calif.) endorsement. 
Several Senate Democrats have already announced White House bids, including Sens. Kirsten GillibrandKirsten GillibrandExpanding our health force can save lives and create jobs simultaneously Sanders offers bill to tax billionaires' wealth gains during pandemic Senate Democrats demand answers on migrant child trafficking during pandemic MORE (D-N.Y.) and Elizabeth WarrenElizabeth WarrenBiden campaign says no VP pick yet after bike trail quip Biden edges closer to VP pick: Here's who's up and who's down Democratic convention lineup to include Ocasio-Cortez, Clinton, Warren: reports MORE (D-Mass.), or are viewed as potential 2020 contenders like Sen. Sherrod BrownSherrod Campbell BrownOvernight Defense: Guardsman to testify Lafayette Square clearing was 'unprovoked escalation' | Dems push for controversial Pentagon nominee to withdraw | Watchdog says Pentagon not considering climate change risks to contractors Democrats urge controversial Pentagon policy nominee to withdraw Chamber of Commerce, banking industry groups call on Senate to pass corporate diversity bill MORE (D-Ohio) and independent Bernie SandersBernie SandersThe Memo: Trump team pounces on Biden gaffes The Hill's Campaign Report: US officials say Russia, China are looking to sow discord in election Warren urges investment in child care workers amid pandemic MORE (Vt.), who caucuses with Democrats. 
Asked if he would support Gillibrand, Schumer told reporters that they work "very well" together, but he was not "mixing in" the 2020 fight. 
"I have said to every candidate who has asked me, let a thousand flowers bloom. Let’s get a lot of people out there and see who the best candidate to beat Donald TrumpDonald John TrumpDeWine tests negative for coronavirus a second time Several GOP lawmakers express concern over Trump executive orders Beirut aftermath poses test for US aid to frustrating ally MORE is. I don’t know who that is right now," Schumer said.