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Democratic presidential candidates expressed their support for Puerto Rico on Twitter following Tuesday's earthquake, while some Democrats in Congress demanded that the Trump administration release aid that had been approved after Hurricane Maria.

The 6.4-magnitude earthquake struck Puerto Rico before dawn Tuesday, killing one person and causing power plant shutdowns on the ailing island.

The earthquake is something of a piling on for Puerto Rico. It is still crippled by Maria, which hit in 2017, its $70 billion debt and a relatively new interim government that was installed after the former governor was ousted amid an email scandal.

On Tuesday, the Federal Emergency Management Administration said that the president had signed an emergency declaration for Puerto Rico because of the quake.

"Puerto Rico has been through too much already. We should forgive their debt, make them a state and rebuild in earnest," presidential candidate Andrew Yang tweeted in one of the bolder responses from the candidates.

His fellow candidates were more tempered. Several referred to the people of Puerto Rico as resilient and empathized with them.

Almost all included jabs at President Donald Trump and his administration and pledged to get the island its due.

"The Trump administration has failed the people of Puerto Rico," Sen. Bernie Sanders, I-Vt., said in his tweet, adding: "We must do everything we can to rebuild."

Former Vice President Joe Biden said it was "unconscionable" that disaster recovery work remained undone and called for delivery of "concrete support" to Puerto Rico.

Puerto Rico has been through too much already. We should forgive their debt, make them a state and rebuild in earnest. https://t.co/nbznCyQveE — Andrew Yang🧢 (@AndrewYang) January 7, 2020

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"I'll fight to ensure they receive the disaster assistance they need and deserve to recover from these earthquakes," Sen. Elizabeth Warren, D-Mass., tweeted.

Pete Buttigieg, the former mayor of South Bend, Indiana, said Puerto Ricans "must be assured the administration will act quickly."

Sen. Amy Klobuchar, D-Minn., said disaster relief should be provided "without delay."

Sen. Cory Booker, D-N.J., issued a call for a public response, saying, "We must be ready to help our fellow Americans."

Other Democrats in Congress demanded the release of $8.3 billion in disaster recovery money in a letter sent to Housing and Urban Development Secretary Ben Carson. Congress approved the money in response to the destruction by hurricanes Maria and Irma, which sideswiped the island 16 days before Maria hit.

By law, the money was supposed to have been released by Sept. 4, 2019, according to the lawmakers, who said in a letter circulated by Rep. Nydia Velázquez, D-N.Y., that HUD's "continued inaction puts at risk the lives of millions of American citizens."

Meanwhile, some Republicans in Congress urged Trump to approve Puerto Rico Gov. Wanda Vázquez's request for a disaster declaration following the earthquake. Republican Sens. Marco Rubio and Rick Scott of Florida — a state with a significant Puerto Rican population — as well as Puerto Rico's nonvoting congressional delegate, Jenniffer González-Colón, urged Trump to instruct federal agencies to provide necessary support.

'Here we go again'

San Juan Mayor Carmen Yulín Cruz, speaking by phone from San Juan, said that while her city had not seen structural damage, people were very worried.

Cruz is known for having called out Trump for what she characterized as his administration's slow and inadequate response to Maria, which killed thousands of people. She said she was jolted awake as her bed jumped around her bedroom during the earthquake Tuesday morning.

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Cruz said that when she left the house at about 6:15 a.m., she found long lines at gas stations. People are buying up water at supermarkets amid warnings that the power plant that generates power for San Juan had been significantly damaged.

She said the latest disaster left Puerto Ricans feeling that just as they were starting to breathe, "here we go again."

In other parts of the island, some bridges and roads that were weakened or made more fragile by the hurricanes collapsed after the earthquake.

"We have not received the reconstruction money that has been allocated for Puerto Rico, and in that respect, I urge every member of Congress, whether Democrat or Republican — this is an issue of justice — to ask and demand that the president of the United States declare portions, if not the entirety, of Puerto Rico a state of emergency," Cruz said.

The emergency declaration signed by Trump makes made available emergency aid for the island and authorizes the agency to coordinate relief efforts.

Cruz said the earthquake is a new opportunity for the federal government to get it right.

"We do have to push on. You either stand up and do what must be done or you stand down and let things happen to you," Cruz said. "We are resilient. We are fighters. We know more people are with us than are against us."

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