Was just a matter of time Obama says!

  President Barack Obama formally endorsed Hillary Clinton's bid for the White House on Thursday, praising his former secretary of state's experience and grit, and urging Democrats to unite behind her in the fight against Republicans in the fall. (Jun AP

WASHINGTON — There was never any doubt President Obama would name Hillary Clinton as his preferred heir apparent. The only question was when he would do it.

For Obama, that decision came Monday night, after the Associated Press reported that Clinton had won enough convention delegates to clinch the Democratic nomination. The next day, Obama sat down in the White House for a videotaped endorsement message in which he declared, "I'm with her."

The Clinton campaign released that video Thursday afternoon, giving Obama time to break the news to her rival for the nomination, Sen. Bernie Sanders, I-Vt. Obama met with Sanders in the Oval Office Thursday morning. "It is fair to say that Senator Sanders was not at all surprised by today's announcement," White House Press Secretary Josh Earnest said.

"I had a great meeting with him this week," Obama said in the video, his use of the past tense only reinforcing the awkwardness of the endorsement's timing. "I thanked him for shining a spotlight on issues like economic inequality, and the outsized influence of money in our politics, and bringing young people into the process. Embracing that message is going to help us win in November."

Obama professed neutrality during the primary, even as he repeatedly praised Clinton and treated her nomination as inevitable.

As far back as April 2015, Obama said Clinton was a "formidable candidate" in 2008. "She was a great supporter of mine in the general election. She was an outstanding Secretary of State. She is my friend. I think she would be an excellent president," he said.

In a January interview with Politico, Obama praised Clinton as "wicked smart," while suggesting that some voters were attracted to Sanders as a bright new "shiny object." (That interview prompted an earlier Oval Office meeting with Sanders in an effort at even-handedness.)

"Next year at this time, someone else will be standing here in this very spot, and it's anyone's guess who she will be," he joked at the White House Correspondents' Dinner in April.

And on Thursday, Earnest hinted that Obama had privately supported Clinton all along. "I did not ask the president about which box he checked on his ballot, but I'm not aware that he changed his mind at any point during the primary," he said.

But Obama was also careful not to slight Sanders — or, more importantly, his supporters — coalitions that could be crucial in the fall election. Obama met with Sanders in the Oval Office twice since January, and spoke by phone twice just in the past week. White House Political Director David Simas coordinated the White House outreach with all the Democratic campaigns throughout the process, and his job was to make sure "nobody was surprised" by anything the president said or did, Earnest said.

Presidential endorsements of a successor have usually waited until the nomination contest is decided. President Ronald Reagan endorsed his vice president, George H.W. Bush, on May 12, 1988 — the same day Bush's last challenger, the televangelist Pat Robertson, dropped out. President George W. Bush endorsed John McCain March 5, 2008, the day after the Arizona senator clinched the GOP presidential nomination.

One exception: President Bill Clinton, who endorsed then-Vice President Al Gore 44 days before the Iowa caucuses — but then mostly kept his distance as the Gore campaign worried about the impact of Clinton's personal scandals.

Still, Obama's endorsement seemed to come earlier than Sanders would have liked, as he continues to compete in the District of Columbia primary next Tuesday.

Obama's endorsement message was an explicit call to unify the Democratic Party. "Secretary Clinton and Sen. Sanders may have been rivals during this primary. but they're both patriots who love this country. And they share a vision for the America that we all believe in," Obama said.

"Those are the values that unite us as Democrats. Those are the values that make America great. Those are the values that are going to be tested in this election. And if we all come together in common effort, I'm convinced we won;t just win in November, we'll build on the progress we've made and we will win a brighter future for this country that we love."

The response from the presumptive Republican nominee, Donald Trump, was swift: "Obama just endorsed Crooked Hillary. He wants four more years of Obama — but nobody else does!" he tweeted. ("Delete your account," Clinton responded.)

Obama will meet up with Clinton on the campaign trail next Wednesday in Wisconsin, a state Obama won twice. The Green Bay appearance is the only one on the schedule for now, but Earnest said "I would anticipate that it is only the first of many campaign events between now and November."