President Barack Obama’s choices for replacing Antonin Scalia on the Supreme Court come down to firing up the Democratic base with a decidedly liberal jurist who can’t be confirmed, or offering Senate Republicans a more moderate candidate they could support.

The decision will overshadow Obama’s remaining 11 months in office and shape his legacy. Either choice risks creating unparalleled gridlock with congressional Republicans that would mean Obama’s final days in office are devoured by the bitter partisan warfare he came to Washington to erase.

Based on Obama’s precedent with judicial vacancies, he would be expected to choose a moderate with a shot at ascending to the high court, however unlikely that path might be. Pressure is sure to come from some in his party to take advantage of the inevitable showdown with Republicans -- who have vowed to stop any Obama nominee -- and showcase a nominee who would inspire Democratic activists in the election. 

These Democrats bet they can embarrass Senate Majority Leader Mitch McConnell and Republican presidential candidates for playing politics with what is supposed to be the last remaining unspoiled and nonpartisan institution in Washington, the Supreme Court -- with the White House and control of the U.S. Senate on the line in 2016 elections. McConnell has said he will block any Obama nominee.

Focus on Winning

But choosing a nominee intended almost exclusively to inspire the Democratic Party’s liberal wing would be a sharp break for a White House that to date has focused on winning confirmation for judicial nominees over making symbolic statements, according to three former administration officials, all of whom spoke on condition of anonymity to discuss internal deliberations.

Most of the White House’s past preparatory work on Supreme Court candidates has focused on people with appeal across party lines, one of the former officials said.

As recently as last spring, the White House refreshed vetting a field of 15 to 20 potential Supreme Court picks, one former official said. But there were no specific contingency plans for replacement of a conservative justice in an election year.

Obama said Saturday that he will send a nomination to the Senate despite statements by McConnell and other Republican lawmakers that they won’t vote hold a vote. But there’s also no hurry; the Senate is taking the week off.

‘In Due Time’

“We don’t expect the president to rush this through this week, but instead will do so in due time once the Senate returns from their recess,’’ White House spokesman Eric Schultz said in California, where Obama will open a summit Monday with Southeast Asian leaders.

A Supreme Court nominee who would inspire the Democrats’ liberal wing could address one of the party’s biggest election-year problems: an enthusiasm gap. Republicans are more likely to tell pollsters they plan to vote in November.

That political challenge is underscored by the weakness former Secretary of State Hillary Clinton has shown in early primary contests in Iowa and New Hampshire. While she remains the front-runner in national polls, she has had difficulty rallying party activists to her candidacy. Even with her challenger, Bernie Sanders, claiming to energize a whole cadre of disaffected voters, turnout in the first two Democratic nominating contests was well below 2008 levels, when Obama first ran for the White House.

Political Opportunity

Either way, the Supreme Court vacancy poses an opportunity for Obama and the Democrats, with Senate Republicans arguing that a sitting president with almost a year left in his term should be denied a chance to offer a nominee. 

The president’s party is mobilizing for a confrontation. The White House coordinated messaging strategy in a conference call Sunday with allies who regularly appear on television, said one Democratic Party operative, who asked for anonymity because the call wasn’t public.

But the administration’s inclinations toward cross-party appeal could be seen in unofficial lists of potential nominees floating in Washington following news Saturday of Scalia’s death while on vacation in Texas. Controversial heroes of the left such as Senator Elizabeth Warren and California Supreme Court Justice Goodwin Liu were missing.

Senate Contests

A nominee the administration can present as a moderate has the potential to put Republicans in a bind both on the national stage and in key Senate races that could determine control of the Senate by underscoring Democratic portraits of Republican intransigence, said Anita Dunn, a former Obama communications strategist.

"It injects front and center the obstructionism issue in a real way for
people," Dunn said.

Democratic Senate leaders were already laying groundwork for such a strategy
on television Sunday.

“I believe that many of the mainstream Republicans, when the president nominates a mainstream nominee, will not want to follow Mitch McConnell over the cliff," Senator Charles Schumer of New York said on ABC’s "This Week. “When you go right off the bat and say, ‘I don’t care who he nominates, I am going to oppose him,’ that’s not going to fly," he added.

Political Blowback

Senator Patrick Leahy of Vermont, a senior Democrat on the Judiciary Committee, predicted electoral blowback for the GOP.

“If the Republican leadership refuses to even hold a hearing, I think that is going to guarantee they’re going to lose control of the Senate," Leahy told CNN.

Texas Senator Ted Cruz, one of the leading contenders for the Republican presidential nomination said he wants to make the 2016 election a referendum on the Supreme Court. “If the Democrats want to replace this nominee, they need to win the election,’’ he said Sunday on ABC’s “This Week’’ program.

Republicans hold 54 seats out of 100 in the Senate, giving them the power to carry through on the threat. That’s if they stick together. There are 24 Republican Senate seats up for election in November and only 10 currently held by Democrats.

Republican Incumbents

Five incumbent Republicans facing voters in states won twice by Obama are under the most pressure: Mark Kirk of Illinois, Ron Johnson of Wisconsin, Kelly Ayotte of New Hampshire, Rob Portman of Ohio and Pat Toomey of Pennsylvania. Republicans also are defending an open seat in Florida, where Marco Rubio has declared he won’t run for re-election.

Johnson and Ayotte on Sunday said that they stand with McConnell.

The administration has emphasized ethnic and gender diversity in judicial appointments even as it has avoided ideological roadblocks to confirmation, setting records in its appointments of women, minorities and openly gay judges. Both Obama’s previous Supreme Court appointees are women, one of whom is the first Hispanic to serve on the court, Sonia Sotomayor.

That suggests a possible template for an election-year appointment who would show deference to Republican ideological concerns while appealing to ethnic or gender pride. One such potential nominee is Indian-born Sri Srinivasan, 48, an Obama appointee who in 2013 was confirmed 97-0 to a seat on the District of Columbia federal appeals court and would be the first Asian-American Supreme Court justice. Another contender with potential bipartisan appeal is Srinivasan’s appeals court colleague, Merrick Garland, 63, whom Obama considered for Supreme Court openings in 2009 and 2010. At the time, Garland had support from prominent Republicans, including Senator Orrin Hatch of Utah.

Even if an Obama nominee isn’t confirmed before the election, his choice may leave a legacy on the court. Should a Democrat win the presidential election and the nominee demonstrate enough cross-party appeal to overcome a Republican filibuster, he or she would likely be the leading candidate for re-nomination in 2017.

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