Hillary Rodham Clinton picked up endorsements from another major labor group and a longtime ally of Vice President Joe Biden on Saturday.

The International Longshoremen’s Association and Charleston, South Carolina, Mayor Joe Riley announced their support of the Democratic presidential candidate at a Charleston union hall the morning after she was received warmly as the keynote speaker at a local NAACP banquet.

Both events in this early voting state demonstrate the delicate balance Clinton has to maintain between withstanding her closest primary rival, Vermont Sen. Bernie Sanders, and laying the groundwork for a coalition that will win the general election.

The same alliance twice elected President Barack Obama: enthusiastic turnout from minorities, women and young voters, with just enough additional support from white working-class voters of all ages.

At the ILA union hall, Clinton credited unions with bringing fair working conditions and better wages that “raised hopes … and gave people a chance to have a better life.” And she assailed Republican-led efforts to “dismantle collective bargaining rights.”

Clinton has attracted more support from organized labor since coming out against the Obama administration’s Pacific rim trade agreement that unions loathe and that Sanders opposed long before Clinton.

Sanders draws enthusiastic crowds with his praise of the working class and indictment of corporate greed. On Saturday, he was in New Hampshire, where the postal workers’ statewide union and two local trade unions have endorsements.

“They understand that at a time when the middle class of this country continues to disappear, we need an economy that works for the middle class and not just the top 1 percent,” Sanders said in a statement.

Yet national labor groups have been slow to back him formally.

The nation’s largest federation of unions, the AFL-CIO, has yet to endorse a candidate. The umbrella group includes the ILA, the teachers unions and public employee unions that have endorsed Clinton.

Labor is particularly important to Sanders’ bid, given his difficulty in attracting significant support from another key Democratic constituency: African-Americans. Clinton has put on display her longstanding relationships with black voters in recent weeks.

At the NAACP and elsewhere, she’s pitched an overhaul of the U.S. criminal justice system and her condemnation of Republican policies on voting rights and ballot access.

She used the NAACP banquet Friday to praise Charleston residents for their “grace and resilience” after the June massacre in which a white gunman killed the pastor and eight others at a historic black church. She renewed her call for “common-sense” gun restrictions, like making background checks more thorough and extending them to sales at gun shows.

Yet on Saturday, in front of a more racially mixed audience, she also noted that she was raised around firearms. “My dad taught me to shoot,” she said. And, appealing beyond the Democratic base, she said, “I’m looking for support from responsible gun owners.”

Likewise, Clinton seemed to aim her labor arguments beyond her friendly audience at the ILA local hall. She compared collective bargaining rights to the government’s “separation of powers” enshrined in the Constitution. “We need that same balance of power in the economy,” she said.

And in an economic argument aimed both at partisans and independents, she alluded to economic growth and reductions in unemployment and the deficit during the terms of her husband, former President Bill Clinton, and President Barack Obama.

“The facts speak for themselves,” she said. “The economy does better when we have a Democrat in the White House.”

On gender pay equity, she argued that it’s a “family issue” and “an economic issue” rather than “a women’s issue.” But she roused her supporters with the conclusion: “Sometimes Republicans accuse me of playing the gender card. I say if standing up for equal pay for equal work is playing the gender card, then deal me in.”

Kay Koonce, a Democratic National Committee member from Charleston and a longtime Clinton supporter, said Clinton is effectively unifying multiple Democratic constituencies while positioning herself for the wider electorate.

She agreed it’s a difficult needle to thread, particularly on guns: The very working-class whites that Clinton wants to reach in swing states like Ohio, North Carolina, Colorado and Virginia are same kinds of voters who don’t identify with national Democrats on many cultural issues, including guns.

“If anybody can break through on that for Democrats, I think it’s her,” Koontz said.

(AP)