The 2016 Republican field is wide open

Calendar is king: Why the details of the primary dates and the map are so important to watch … Bernie Sanders is officially joining the race … Sanders talks to NBC’s Andrea Mitchell about his platform, Hillary Clinton and why he’s running as a Democrat … But is it Sanders or O’Malley who ends up being Clinton’s chief Democratic rival? … David Wildstein reportedly set to plead guilty in the Bridgegate mess … and the Iran bill could hit a big snag with “poison pill” amendments form 2016 hopefuls.

FIRST THOUGHTS.

*** Why the primary calendar could be king in 2016 GOP race: Here’s one reason why we’re excited to cover the 2016 presidential race: We have absolutely no idea who is going to win the Republican presidential nomination. Jeb Bush? Scott Walker? Marco Rubio? Someone else? And because it’s THAT wide open with no true frontrunner, the 2016 primary calendar could very well be king. As we discovered on the Democratic side in 2008, the campaign that best maximizes the calendar, map, and delegate hauls will probably be the nominee. Already, one likely move — Nevada becoming a primary contest instead of a caucus, which hurts Rand Paul — would have consequences. And here are three other primary calendar storylines to watch, with the important caveat that the calendar isn’t going to be finalized until later this year:

• The March 1 “SEC Primary”: After Iowa, New Hampshire, Nevada, and South Carolina, this will be the next important calendar date. And there are two schools of thought about these contests: 1) Either one candidate dominates and emerges as the frontrunner, or 2) Because their delegate hauls are proportional, it’s possible that the top contenders evenly divide up the delegates — and thus no one wins, and we all move to the next contests. Worth noting: While this March 1 date earned the moniker “SEC Primary” due to the all the Southern states expected to participate, right now Frontloading HQ shows the states to be Tennessee, Texas, Virginia, Oklahoma, and Vermont. So it’s really the SEC/Big 12/ACC Primary.

• The March 15 “winner-take-all” contests: March 15 is the first window where states can award delegates on a winner-take-all basis. The March 15 states could be Florida (Bush vs. Rubio!), Illinois, Missouri, Ohio, and maybe even Wisconsin. This matters because if Bush and Rubio do duke it out in the expensive Sunshine State, another candidate (say Walker) could decide to concentrate on the other states like Illinois, Missouri, Ohio, and Wisconsin and emerge as the big delegate winner on March 15. (But a caveat to keep in mind: “Winner-take-all” doesn’t always mean what it sounds like, with some states choosing to dole out delegates by congressional district rather than on a statewide basis.)

• The shortened nominating calendar: After the party’s 2012 loss, the Republican National Committee decided to shorten its nominating calendar. The logic: The long-ish slog between Mitt Romney and underfunded Rick Santorum didn’t do the party any good, especially when facing an incumbent Democratic president. But the unintended consequence of a shortened nominating calendar is that about 70% of the delegates might not be decided until May. And with no incentives for candidates to drop out (because of well-financed Super PACs supporting them or with a convention in July), it’s possible that no one candidate has a majority of delegates by May or even later.  Does that mean a contested convention, with no candidate able to snag enough support to nail down the nomination? Maybe not, but it could mean behind-the-scenes agreements and forced alliances between campaigns as they limp to the finish line, or it could mean the ultimate winner has to pick a running mate who otherwise wouldn’t be their first choice.

*** Bernie Sanders makes his presidential announcement: The Vermont independent, who’ll run as a Democrat, makes it official today via an email to supporters. He’ll emphasize his focus on income inequality, according to excerpts of the email, with an explicit mention of the one percent/99 percent divide. “The people at the top are grabbing all the new wealth and income for themselves, and the rest of America is being squeezed and left behind,” he’ll say. Other issues he’ll highlight in his announcement message: money-in-politics (“billionaires rig the system by using their Super PACS to buy politicians and elections”) and climate change (“the central challenge of our time and our planet.”). As our colleague Perry Bacon writes, Sanders won’t win, but his presence in the race will mean more discussion of progressive issues like expanded Social Security and further financial reforms – which means more pressure on Hillary Clinton to enumerate specifics about her own domestic agenda. But because he’s been reluctant to take too much aim at Clinton yet (more on that below), it’s worth wondering how much his run is also about elevating his own status as progressive leader in the Senate, too.

*** Why he’s running: In an interview with NBC’s Andrea Mitchell, Sanders said he doesn’t see his presidential bid as a challenge to Hillary Clinton. “It’s addressing the very, very serious crises facing our country, crises that have to be addressed.  Look, for the last 40 years the America middle class has been disappearing.  We have people working longer hours for lower wages.  And at the same time, we have seen a huge increase in income and wealth inequality such that the top 1% are now earning 99% of all new income generated in this country,” he said. He told Mitchell that questions about Hillary Clinton’s fundraising and the Clinton Foundation are legitimate questions but added “But I think we have to ask what the motives are of the Koch brothers and Republican billionaires who frankly want to end Social Security, end Medicare, end Medicaid and give more tax breaks to billionaires.”And he explained why he’s running as a Democrat – instead of an independent:“The reason is pretty simple.  I am not a billionaire.  To run outside of the two-party system would require enormous sums of money and a great expenditure of energy and time just to get on the ballot.”

*** Who ends up being Clinton’s chief rival? With Sanders and potential 2016 Democratic candidate Martin O’Malley both in the headlines today, we’re getting a view of how each one will be a contrast to Clinton throughout the nomination process. And it’s not clear yet which one will be the more important rival. With Sanders, she’ll have to consider how far to turn the progressive dial in her rhetoric and policy proposals. O’Malley can argue that he’s a viable alternative to Clinton who can check the progressive boxes and still be competitive. But O’Malley’s entry into the national conversation this week hasn’t gone as smoothly as the former Baltimore mayor must have hoped. Rather than a narrative about returning to Baltimore as healing and unifying leader, much of the coverage has focused on those who blame his zero-tolerance policies for the city’s simmering tensions. As NBC’s Leigh Ann Caldwell writes, “He is positioning himself to the left of Clinton on economic issues but on the issue of policing and criminal justice, O’Malley’s past could be more of a black mark than a boon to the progressive voter he’s attempting to court.”

*** David Wildstein reportedly set to plead guilty: Chris Christie has been struggling to score positive headlines, and it’s about to get even worse. Bloomberg reports that former Port Authority official and onetime Christie ally David Wildstein is set to plead guilty for charges related to the Bridgegate scandal. That suggests that he may be cooperating with prosecutors and offering more information about the plot to snarl traffic on the George Washington Bridge back in 2013.  Speaking to reporters yesterday, Christie reiterated that he knew nothing in advance about the lane closures, adding “Whenever anything does occur, we’ll react to it. But I know what the truth is, so I’m not the least bit concerned about it.” But regardless of the fallout from Wildstein’s plea, “Christie Ally Pleads Guilty” is not the kind of headline you want when you’re trying to convince donors and political operatives of your viability in a presidential race.

*** Iran bill faces its next challenge: 2016 presidential ambitions: After all the meticulous negotiations to maintain enough support for the Senate’s Iran nuclear-approval bill, it could still be derailed because of presidential politics. 2016 hopefuls Marco Rubio and Ted Cruz are pushing for amendments to the legislation that critics say are “poison pills” designed to win them conservative accolades even if they risk scuttling the agreement, National Journal writes. While many of their colleagues agree with the substance of the amendments — (one of Rubio’s would require Iran to accept Israel’s right to exist) – there’s real concern that forcing votes on the measures would ruin the Senate’s one shot of weighing in on the overall deal. Rubio argued yesterday that pushing issues that make some lawmakers squeamish is the stuff of political bravery, saying “If you don’t want to vote on things, don’t run for the Senate.”  But folks like possible 2016 rival Lindsey Graham aren’t being shy about dismissing Rubio’s strategy as “immature” and selfishly focused on scoring political points. The question might come down to: which argument do voters buy?

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OFF TO THE RACES: Bush makes his case for Hispanic support

BUSH: He told a convention of Hispanic evangelicals that undocumented immigrants should be able to get legal status.

CLINTON: The New York Times: “Aides to former President Bill Clinton helped start a Canadian charity that effectively shielded the identities of donors who gave more than $33 million that went to his foundation, despite a pledge of transparency when Hillary Rodham Clinton became secretary of state.”

Here’s a wrap from yesterday – from one of us(!) – about Hillary Clinton’s big speech on criminal justice reform.

The Des Moines Register writes about local reaction to her proposals – on A1.

“Hillary Rodham Clinton had once planned to wait until May to hold her first fund-raising events. But in the last two weeks, she has moved up her schedule, primarily out of concern about Jeb Bush’s extensive super PAC fundraising, according to donors and people in contact with the campaign,” writes the New York Times.

CRUZ: He’s picked up the endorsement of former Iowa secretary of state Matt Schultz, the Quad City Times reports.

O’MALLEY: Our own Leigh Ann Caldwell writes about the former Baltimore mayor’s record and how some residents aren’t happy that he’s back in town.

And the New York Times looks at how criticism of his zero-tolerance police strategy could be problematic for him. “For a politician whose potential candidacy has received little attention, it was hardly the spotlight he had hoped for. But Mr. O’Malley has nevertheless embraced the moment, arguing that his in-the-trenches familiarity with the urban issues exposed by the riots gives him a unique voice in the coming presidential election.”

Bloomberg spent some time with the former mayor and digs into the effects of his past policies.

SANDERS: Perry Bacon Jr. writes that Bernie Sanders won’t win, but his ideas might.

OBAMA AGENDA: The latest from Baltimore

The latest from Baltimore, from the Sun: “After arresting more than 200 people this week while bringing order to the streets of Baltimore, police said Wednesday they had to let half of them go. A police spokesman said that amid the bedlam of Monday’s unrest, it was difficult to document which officers had arrested which suspects and for precisely what reasons. Gov. Larry Hogan took steps to keep people jailed for two days without charges — nearly twice as long as usually allowed — but it still wasn’t long enough for officers to sort out what happened.”

The Washington Post, on yesterday’s economic growth data.

CONGRESS: Done deal

Republicans have a deal on a joint budget, and it could be approved as early as this week.

From the AP: “Congressional Republicans are divided over how to respond to an approaching Supreme Court decision on President Barack Obama’s health care law, even as growing numbers concede that their long-sought goal of repealing the statute will have to wait.”

NBC News’ Carrie Dann contributed reporting.