About an hour and a half after President Obama met Bernie Sanders at the White House, Obama endorsed Hillary Clinton for president. Today's announcement was ready to go in a pre-produced video.

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BARACK OBAMA: Look; I know how hard this job can be. That's why I know Hillary will be so good at it. In fact, I don't think there's ever been someone so qualified to hold this office. She's got the courage, the compassion and the heart to get the job done. And I say that as somebody who had to debate her more than 20 times.

SHAPIRO: NPR national political correspondent Mara Liasson is back here in the studio once again to talk about this latest sign the general election is on. Hi, Mara.

MARA LIASSON, BYLINE: Hi, Ari.

SHAPIRO: This endorsement was clearly done hand-in-hand with the Clinton campaign. Did the candidate herself say anything about it?

LIASSON: Yes, she did to our own Tamara Keith today in an exclusive interview when she talked about what she wants Obama to do for her in the campaign.

HILLARY CLINTON: I know he is raring to get out there and start campaigning, and I really look forward to campaigning with him.

LIASSON: That is the understatement of the year...

SHAPIRO: (Laughter).

LIASSON: ...Because President Obama is very popular with the part of the Democratic base that Hillary Clinton really needs to win over, and that is young people. Bernie Sanders just clobbered her with young people during the primaries.

Obama is also a popular sitting president whose approval ratings are hovering around 50 percent. And Clinton and Obama are going to start campaigning together very soon. They're going to go to Green Bay, Wis., on Wednesday, the day after the last primary here in the District of Columbia next Tuesday.

As to what role she envisions for Bernie Sanders — maybe a primetime speaking slot at the convention. She wouldn't say. She'd only say, we have a lot to discuss.

SHAPIRO: Bernie Sanders is still running though.

LIASSON: He is still running, and he was at the White House today and on Capitol Hill meeting with Democratic Senate Leader Harry Reid. He's holding a rally tonight in Washington, D.C. And the effort of the White House and the Clinton campaign and other Democratic leaders has been to get Sanders to exit the race without antagonizing his supporters so the party can unite.

Today Sanders didn't say anything about leaving the race. Up until now, he said he wants to stay until the convention. But he was very conciliatory when he emerged from the White House, and he seemed to be going out of his way to communicate to his supporters that he did not feel mistreated.

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OBAMA: What they said in the beginning is that they would not put their thumb on the scales. And in fact, they kept their word, and I appreciate that very, very much.

SHAPIRO: It seems that other prominent Democrats have moved on from the primary though. Their eyes are on Donald Trump.

LIASSON: Yes, that's right. Now that Clinton has beaten Sanders by every metric he has laid down for her — pledged delegates, votes cast contests won — now there's going to be a lot of other big, prominent progressive leaders who will join Clinton on the campaign to defeat Donald Trump — first and foremost Elizabeth Warren, who is as much of a hero to the left wing of the party as Sanders is. She is endorsing Hillary Clinton tonight.

Sanders then will have to decide what role he wants to play. He has a big role to play at the convention, designing the platform. He also has to decide if he will become a full partner to Clinton the way she did with President Obama eight years ago.

SHAPIRO: NPR national political correspondent Mara Liasson — thanks, Mara.

LIASSON: Thank you.

奧巴馬總統在白宮同伯尼·桑德斯進行了長達一個半小時的會談之后，表態(tài)支持希拉里·克林頓當選總統?？偨y今天的表態(tài)通過提前錄制的視頻宣布。

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巴拉克·奧巴馬：我知道這份工作有多難做。所以我知道希拉里肯定能做好。實際上，我認為沒有人比她更勝任美國總統這一職位。她有完成這份工作的勇氣、同理心和決心。我是依據我和她辯論過20多次的經歷來發(fā)表的立場。

夏皮羅：NPR新聞的國家政治記者瑪拉·利亞森再次來到演播室，她將和我們談談總統大選的最新形勢。你好，瑪拉。

瑪拉·利亞森：你好，阿里。

夏皮羅：顯然這一支持表態(tài)是總統與克林頓的競選團隊攜手發(fā)布的。那希拉里本人有沒有什么回應？

利亞森：有，她今天接受了NPR新聞的塔瑪拉·基思的專訪，她在專訪中談到了她希望奧巴馬在競選中能幫她的事。

希拉里·克林頓：我知道他很少進行公開競選活動，不過我真的很希望和他一起參加競選活動。

利亞森：這是保守說法……

夏皮羅：（大笑）。

利亞森：……因為奧巴馬總統在希拉里·克林頓需要贏下的民主黨選民中非常受歡迎，那就是年輕選民。伯尼·桑德斯剛剛在初選中憑借年輕選民的支持沖擊了她。

奧巴馬是一位受歡迎的在任總統，他的支持率一直保持在50%上下?？肆诸D和奧巴馬很快將一起出席競選活動。二人將于下周三共同出席在威斯康星州格林貝舉行的競選活動，在前一天，也就是下周二將在哥倫比亞特區(qū)進行民主黨最后一次初選。

至于她對伯尼·桑德斯的角色有何設想——也許是在黃金時間在代表大會上發(fā)表講話的機會。她并沒有說。她只說，我們有很多要討論的事項。

夏皮羅：伯尼·桑德斯仍在繼續(xù)參選。

利亞森：他仍在參選。他今天現身白宮，還在國會山同參議院民主黨領袖哈里·瑞德舉行了會談。他今晚將在華盛頓特區(qū)舉行集會活動。雖然白宮、希拉里競選團隊和其他民主黨領導人一直在努力勸說桑德斯退出競選，但是他們并沒有激怒桑德斯的支持者，所以民主黨可以團結在一起。

今天，桑德斯并沒有表示將退出競選。到目前為止，他仍希望能堅持到召開代表大會的那個時候。他離開白宮時很平和，看上去他在特意向他的支持者表明：他并沒有受到不公平對待的感覺。

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奧巴馬：他們一開始就表示不會影響結果。而且他們也遵守了承諾。我真的非常欣賞這點。

夏皮羅：不過看起來其他杰出民主黨人的焦點已經不再是初選了。他們現在都在關注唐納德·特朗普。

利亞森：沒錯?，F在克林頓通過完成桑德斯制定的各個指標而擊敗了他，這些指標包括宣誓代表票、贏得選票比賽等，接下來將有很多杰出的進步派領袖加入克林頓的競選團隊，共同擊敗唐納德·特朗普，首先要提到的是伊麗莎白·沃倫，她對左翼來說是和桑德斯一樣的英雄人物。她今晚表態(tài)支持希拉里·克林頓。

桑德斯必須決定他想扮演什么角色。他在代表大會上要扮演一個重要的角色——設計平臺。另外，他還要決定是否成為克林頓的合作伙伴，就像8年前希拉里和奧巴馬總統做的那樣。

夏皮羅：以上是NPR新聞的國家政治記者瑪拉·利亞森帶來的報道，謝謝你，瑪拉。

利亞森：謝謝你。