We're in Philadelphia as the Democratic convention gets underway. If you're reading this Monday night, trust us: you really, really want to check out the convention live here, at this linkScroll down for tonight's full lineup, which includes Tim Kaine, Michelle Obama, Elizabeth Warren and Bernie Sanders (more on that below.)

You can catch all The Washington Post's live team coverage of the first day of the convention here, here and here.

APPARENTLY IT ISN'T ALWAYS SUNNY IN PHILADELPHIA:

Bernie Sanders supporters show their displeasure for the Trans-Pacific Partnership during the first day of the Democratic National Convention in Philadelphia. (Photo by Michael Robinson-Chavez/The Washington Post)

Thing we learned today: if you are a candidate who spends roughly six months loudly calling your opponent a corrupt, war-backing tool of corporate interests, and roughly one month saying that on reflection, she's definitely better than that other guy, then at the end of that month, some of your supporters may still be stuck on that first thing.

Maybe you find this lesson unsurprising. Then you are not Bernie Sanders.

Here was the scene around the Wells Fargo Center in Philadelphia as the Democratic National convention got underway tonight (the night's official theme: "United Together"):

(The message from some Sanders protesters: 'Never Hillary')

The air was (slightly) cooler inside the arena as proceedings began. Heads were not.

Tonight, Sanders sent his delegates an urgent email, and his supporters an equally urgent text message, asking them to maybe tone down any displays that seemed airlifted straight out of Cleveland. His former campaign team did the same.

Their problem right now appears to be in part that they did such a fabulous job with primary season messaging that not even they can figure out the right pushback.

Earlier today, the Vermont senator gave his delegates the same pitch in person. As Chris Cillizza noted, it did not land well.

"The crowd cheered as Sanders ran through all of the successes he and his self-professed 'political revolution' had run up this year: the millions of votes he won, the reduction in superdelegates, the takeover of state parties by Sanders supporters.

"Then came time for the pivot. Sanders tried to tell the crowd that now was the time to line up behind Hillary Clinton and her running mate, Timothy M. Kaine. Boos cascaded down. Shouts of 'no!' And then a Sanders chant started up.

"Sanders was at a loss. Here he was telling his most loyal supporters what needed to happen next in order to unify the party and beat Donald Trump. And they weren't listening. They wanted revolution. Now, not later.

"What was clear for anyone watching Sanders's unsuccessful attempts to calm the churning among his supporters is that the revolution he started is no longer one he can totally control. Or maybe even control at all. ..."

(Here's what that sounded like)

"To be clear, not every Sanders supporter feels that way. In fact, the vast majority of them tell pollsters they plan to vote for Clinton this fall. But there is without doubt a vocal group here in Philadelphia unwilling to roll over and play nice with the presumptive nominee — no matter what Sanders says they should do.

"That is an issue for Clinton — and for Sanders. A vocal minority in the context of, say, Sanders's speech to the convention tonight could be a major problem for party strategists doing everything they can to present a united front. Anything similar to what happened this afternoon — booing when Sanders mentions the need to support Clinton — would be a major embarrassment for the former secretary of state just days before she is set to formally take the reins of the national party.

"The scariest thing if you are a member of the Democratic establishment? Not even Bernie Sanders seems to be able to control these people. The revolution is still happening for them, and no one can convince them otherwise."

Sanders himself will take center stage Monday night as the night's final speaker. Debbie Wasserman Schultz will no longer take the stage at all, with the Democratic National Committee issuing an apology tonight, following controversy over the contents of leaked emails indicating some staffers openly preferred Hillary Clinton to Bernie Sanders during the primary season.

"The official kickoff began after Baltimore Mayor Stephanie Rawlings-Blake stepped in for outgoing Democratic National Committee Chair Debbie Wasserman Schultz to gavel in the convention at about 4:15 p.m.," reported Sean Sullivan and Anne Gearan.

"Wasserman Schultz stayed offstage following heavy criticism over the leak of a trove of embarrassing DNC emails. She excused herself from gaveling the convention earlier in the day, bowing to heavy opposition from party activists. She also gave up her speaking slot, according to Hilary Rosen, a longtime Democratic operative and friend of Wasserman Schultz.

"'I have decided that in the interest of making sure that we can start the Democratic convention on a high note that I am not going to gavel in the convention,' Wasserman Schultz told the Sun Sentinel newspaper in Florida, which first reported her plans. ..."

Bernie Sanders supporter Michael E. Sparks, 43, of Indianapolis sports a Bernie Sanders tattoo as he participates in a rally in front of City Hall during the first day of the Democratic National Convention in Philadelphia. (Photo by Jabin Botsford/The Washington Post)

Some were disturbed by the content of the DNC leak, which included, among other embarrassing revelations, some behind-the-scenes donor trash talk. Others were more disturbed by the alleged source.

Clinton's campaign has "accused the Russian government of orchestrating the release of damaging Democratic Party records to help the campaign of Republican Donald Trump — and some cybersecurity experts agree," report Tom Hamburger and Ellen Nakashima.

"The extraordinary charge came as some national security officials have been growing increasingly concerned about possible efforts by Russia to meddle in the election, according to several individuals familiar with the situation.

"Late last week, hours before the records were released by the website WikiLeaks, the White House convened a high-level security meeting to discuss reports that Russia had hacked into systems at the Democratic National Committee.

"Although other experts remain skeptical of a Russian role, the hacking incident has caused alarm within the Clinton campaign and also in the national security arena. Officials from various intelligence and defense agencies, including the National Security Council, the Department of Defense, the FBI and the Department of Homeland Security, attended the White House meeting Thursday, on the eve of the email release.

"If the accusation is true, it would be the first time the Russians have actively tried to influence an election in this manner, analysts said...."

And down in Virginia, Donald Trump predicted today's DNC protesters would vote for him (even though — fact check! — they probably won't):

TONIGHT'S CONVENTION LINEUP:

Workers prepare the stage ahead of the 2016 Democratic National Convention in Philadelphia on July 24, 2016. (Reuters/Jim Young)

After 7 p.m. ET:

Pam Livengood, Substance abuse activist

Sen. Jeanne Shaheen (D-N.H.)

Sen. Jeff Merkley (D-Ore.)

(Above: actual party healing update.) (Photo by Toni L. Sandys/The Washington Post)

8 p.m. ET:

Francisca and Karla Ortiz: A mother in the country illegally, and her daughter, a U.S. citizen.

Astrid Silva, Immigration activist.

Rep. Luis Gutierrez (D-Ill.)

Jason and Jarron Collins, pro basketball players

ShareFile founder Jesse Lipson

Nevada State Sen. Pat Spearman

Sen. Bob Casey (D-Pa.)

Chillicothe, Ohio, mayor Luke Feeney

Sen. Kirsten Gillibrand (D-N.Y.) 

Sen. Al Franken (D-Minn.)

Anastasia Somoza, disability rights activist

Actress Eva Longoria

Sen. Cory Booker (D-N.J.)

Cheryl Lankford

(Sanders supporter on the convention floor.) (Photo by Jabin Botsford/The Washington Post)

10 p.m. ET

First lady Michelle Obama

Rep. Joe Kennedy III (D-Mass.)

Sen. Elizabeth Warren (D-Mass.)

Rep. Keith Ellison (D-Minn.)

Sen. Bernie Sanders of Vermont

YOUR DAILY TRAIL PIT STOP: The Democratic convention and Republican conventions are so different that sometimes you have to actively remind yourself that they are two parties in the same country, running candidates for the same office. There are too many differences to list, especially since we have a day job to get back to right now, but one of the starkest this year has been the makeup of the speaker list. After a week in Cleveland light on both celebrities and elected officials, there were plenty of the former on hand tonight, and a few of the latter — including Philadelphia's own Boyz II Men. To kick off your convention week, here's a little Motown Philly. (You're welcome!)