In editorials published Saturday, the paper laid out the case for each candidate. The endorsement for Clinton received top billing on the paper's website, and gave a more detailed impression of the Democratic field.
"Hillary Clinton would be the first woman nominated by a major party. She served as a senator from a major state (New York) and as secretary of state — not to mention her experience on the national stage as first lady with her brilliant and flawed husband, President Bill Clinton," the editorial board wrote. "The Times editorial board has endorsed her three times for federal office — twice for Senate and once in the 2008 Democratic presidential primary — and is doing so again with confidence and enthusiasm."
"In the end, though, Mr. Sanders does not have the breadth of experience or policy ideas that Mrs. Clinton offers. His boldest proposals — to break up the banks and to start all over on health care reform with a Medicare-for-all system — have earned him support among alienated middle-class voters and young people," the editorial said. "But his plans for achieving them aren't realistic, while Mrs. Clinton has very good, and achievable, proposals in both areas."
"The third Democratic contender, Martin O'Malley, is a personable and reasonable liberal who seems more suited for the jobs he has already had — governor of Maryland and mayor of Baltimore — than for president."
When it came to Kasich's endorsement, the paper was less optimistic and more pragmatic.
"Gov. John Kasich of Ohio, though a distinct underdog, is the only plausible choice for Republicans tired of the extremism and inexperience on display in this race," the editorial board wrote.
The piece condemned other candidates on the Republican slate, starting with Donald Trump, accusing him of making up his policy proposals as he goes along.
"At a meeting with The Times's editorial writers, Mr. Trump talked about the art of applause lines," the editorial board said. "'You know,' he said of his events, 'if it gets a little boring, if I see people starting to sort of, maybe thinking about leaving, I can sort of tell the audience, I just say, 'We will build the wall!' and they go nuts.' "
The editorial board slammed Sen. Ted Cruz, R-Texas, the second-place candidate in the race, for orchestrating a government shut down and alienating his colleagues in the Senate, all during his first term.
"Ted Cruz's campaign isn't about constitutional principles; it's about ambition," the editorial board wrote.
As for the rest of the field, the board said the litter of candidates was "battling for survival."
While saying Kasich is "no moderate," the piece cited his experience in the House as well as his track record as governor.
"While Republicans in Congress tried more than 60 times to kill Obamacare, Mr. Kasich did an end-run around Ohio's Republican Legislature to secure a $13 billion Medicaid expansion to cover more people in his state," the board said, praising the positive tone of Kasich's campaign as a rarity among the Republicans.
The endorsements come two days before the Iowa caucuses on Monday.