People walk across a flooded street in Juana Matos, Puerto Rico, on Sept. 21 as the country faced dangerous flooding and an island-wide power outage after Hurricane Maria. (Hector Retamal/AFP/Getty Images)

In the coming days, Puerto Rico is set to ask for several billion dollars in federal relief after two major hurricanes, as officials acknowledge that the months-long recovery may compel more residents to abandon an already economically distressed island.

The wind and rain from hurricanes Irma and Maria have compounded other significant concerns for the island of 3.4 million people: a double-digit unemployment rate, a looming shortfall in Medicaid funding, a bankrupt electric company and stricter ­federal oversight of the island's already debt-ridden finances. These issues are perennial but mostly overlooked in Washington.

"We have to begin to think in the worst possible terms, between power restoration, critical infrastructure, housing assistance, the need to airlift critical medical ­patients out of the island to the mainland, seniors, things like that," said Sen. Marco Rubio (R-Fla.), whose state is home to more than 1 million Puerto Ricans.

But over the next several months, "the combination of the financial crisis, the health-care crisis and now these two natural disasters, it's a recipe for a lot of people to feel that they're hopeless and they need to come to the [mainland] United States," said Rep. Nydia M. Velázquez (D-N.Y.), whose Brooklyn-area district has a significant Puerto Rican constituency. Velázquez, who is awaiting news about family members on the island, warned that if legislation addressing the economic problems isn't coupled with federal hurricane relief, "we're going to have an unprecedented number of people who will continue to leave the island."

As a U.S. commonwealth, Puerto Rico has a nonvoting member of the House and no U.S. senators. It does, however, benefit from a network of Democrats and Republicans who have roots on the island, own property there or represent states and districts with large voting blocs with Puerto Rican heritage.

"Puerto Rico doesn't have a senator, so we've always treated it as a place we care about a lot," Rubio said. 

About 80,000 Puerto Rico residents moved to the mainland United States last year, part of an exodus driven by the island's devastated economy. Most of them relocated to Florida — another reason for lawmakers such as Rubio to worry about the island.

President Trump on Thursday declared a major disaster across at least 55 municipalities in Puerto Rico and is expected to inspect damage there in the coming days, said Rubio and others familiar with his plans.

Carlos Mercader, a Washington-based spokesman for Puerto Rico Gov. Ricardo Rosselló, said officials are unable to make basic estimates of the potential costs, but "we know it's going to be in the billions."

In Florida, the arrival of thousands of island transplants has transformed cities such as Orlando and Kissimmee and is changing local and national politics. Puerto Ricans are U.S. citizens who can participate in presidential primaries but cannot vote for president while living on the island. Once they move to the mainland, they are eligible, so Democrats and Republicans in Florida eagerly sought out new arrivals last year, urging them to register to vote in the 2016 election.

Rep. Darren Soto (D), the first Floridian of Puerto Rican descent to serve in Congress, was elected last year on the strength of the booming Puerto Rican vote in the Orlando area. "We've anticipated we'll see tens of thousands of folks here at least temporarily," he said. "Many were, I'm sure, already contemplating the move, but this will push them over the top."

Soto has been working with state Rep. Robert Asencio (D), who represents parts of west ­Miami-Dade and Kendall and who warned that the arrivals will "put a strain on existing services."

"It may even result in the state of Florida requesting more money to the federal government for relief," he added.

Gov. Rick Scott (R) has been in touch with Rosselló about ­providing relief, and the state is "100 percent committed to work with counties and local governments regarding potential needs, such as shelters and resources," spokeswoman Kerri Wyland said in a statement. But Florida is still dealing with a disaster recovery effort of its own in the aftermath of deadly Hurricane Irma, which left homes destroyed and millions without power.

In Congress, Puerto Rico is represented by Jenniffer González-Colón, who caucuses with Republicans. In addition to Velázquez and Soto, several other Puerto Ricans serve in Congress: Reps. Luis V. Gutiérrez (D-Ill.), Raúl R. Labrador (R-Idaho) and José E. Serrano (D-N.Y.).

Gutiérrez and Velázquez called on the Trump administration to temporarily suspend the Jones Act, which requires all cargo transported between U.S. ports be carried on American ships, so that medicine, food and other supplies can reach the island quickly.

The island is reeling from a "Medicaid cliff" that is set to leave a nine-figure funding shortfall to pay for health-care services next March. Congress provided nearly $300 million in relief as part of a federal spending package in the spring. 

Federico de Jesús, a Puerto Rican Democratic political consultant in Washington, said that despite the devastation, there may be a "silver lining," because when hurricanes hit, "all of these issues come to the fore. People who don't think about Puerto Rico in D.C. start to think about it."