WASHINGTON (AP) — Senate Democrats on Thursday blocked the first bipartisan energy bill in almost a decade after majority Republicans balked over sending hundreds of millions of dollars in emergency aid to Flint, Michigan, to fix and replace the city's lead-contaminated pipes.

The impasse hardened an increasingly partisan response to the water crisis in Flint as Democrats press for swift help for a majority African-American city of 100,000 and point to the past, rapid response of Republicans to natural disasters in Texas and Florida. Republicans maintained that it was premature to send money until Michigan figures out what it needs and wrong to stall the energy bill.

"One hundred thousand people in Flint, Michigan, have been poisoned, and Republicans do nothing" to help them, said Senate Democratic Leader Harry Reid of Nevada. "Nine thousand little children ... have been poisoned. Still, Senate Republicans refuse to help."

The vote was 46-50, short of a number necessary to move ahead on the comprehensive legislation. The bill promotes a wide range of energy, from renewables such as solar and wind power to natural gas and hydropower. The legislation also would speed federal approval of projects to export liquefied natural gas to Europe and Asia and boost energy efficiency.

Senate Majority Leader Mitch McConnell, R-Ky., said Republicans and Democrats would continue negotiations through the weekend in hopes of salvaging the energy bill.

Democrats proposed a $600 million aid package for Flint last week, but Sen. Debbie Stabenow, D-Mich., said they agreed earlier this week to cut that proposal in half.

Sen. John Cornyn of Texas, the second-ranking Republican, said it was too early to provide funds.

"The fact of the matter is, the state of Michigan and the city of Flint don't yet know what they need to do to fix the problem or how much it will cost," Cornyn said.

Flint is under a public health emergency after its drinking water became tainted when the city switched from the Detroit water system and began drawing from the Flint River in April 2014 to save money. The impoverished city was under state management at the time.

Water was not properly treated to keep lead from aging pipes from leaching into the supply. Some children's blood has tested positive for lead, a potent neurotoxin linked to learning disabilities, lower IQ and behavioral problems.

Michigan has approved $37 million in emergency funding for Flint for the current fiscal year. Gov. Rick Snyder is expected to propose an additional $30 million in state funding to help Flint residents pay their water bills.

President Barack Obama has said that about $80 million in federal funding is being made available to Michigan for investment in water system upgrades. It's not clear how much money would go to Flint.

Democrats have said officials would have acted sooner if Flint were wealthier and its population predominantly white. Flint, 60 miles north of Detroit, is 57 percent black, and 42 percent of its residents live in poverty.

The Republican governor has dismissed those suggestions, but the questions remain.

House Minority Leader Nancy Pelosi, D-Calif., compared the Flint emergency to Hurricane Katrina in 2005, when President George W. Bush was criticized for a lackadaisical federal response.

"Katrina was a natural disaster. How it was handled was a man-made disaster," she said Thursday.

Underscoring the political stakes of the Flint response, several Republican senators vulnerable in their re-election bids voted with the Democrats, including Sens. Kelly Ayotte of New Hampshire, Pat Toomey of Pennsylvania and Rand Paul of Kentucky. The lone African-American Republican, Sen. Tim Scott of South Carolina, also voted with Democrats.

Sen. Gary Peters, D-Mich., said the crisis in Flint demands immediate action.

"If any of my colleagues here saw a tragedy like this in their home state, they would be standing here doing everything in their power to deliver assistance, whether the crisis was natural or man-made," he said in an impassioned speech on the Senate floor.

Lawmakers approved millions in federal emergency aid for Texas after a catastrophic 2013 blast at a fertilizer plant, Peters and other Democrats said.

"The people of Michigan, the people of Flint, through their tax dollars have stood with the people of Texas," Stabenow said. "This is as much of a national emergency as if a tornado or a hurricane ripped up a town, because the entire town can't drink the water and children are being poisoned."

Sen. Lisa Murkowski, R-Alaska, chairwoman of the Senate Energy and Natural Resources Committee, said discussions on ways to help Flint were continuing.

"We want to get this solved," she said, adding that it was counterproductive for Democrats to block an energy bill that has been in the works for more than a year.

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