Story highlights Lexington Mayor Jim Gray is seen by Democrats as their best hope of ousting Rand Paul

"In Washington, Senator Paul has put his own ambition ahead of Kentuckians," Gray said

Washington (CNN) The mayor of Lexington, Kentucky, announced Tuesday he will challenge Rand Paul for the Senate, giving Democrats their best shot yet at defeating the Republican incumbent.

"As your Senator I won't just talk, I'll listen. I'll offer common sense solutions. And I'll work to restore the American dream for every family in Kentucky," the wealthy Jim Gray, who had been courted by the party to run, said in a statement.

The mayor, who filed the paperwork to run on Tuesday for what remains an uphill battle, said Paul has forgotten Kentucky in his pursuit of the White House.

"In Washington, Senator Paul has put his own ambition ahead of Kentuckians and is behind policies that would hurt Kentucky families," Gray said. "He voted for a plan that would double healthcare costs for our seniors and supports privatizing Social Security. He supported massive cuts of over $160 billion to our military, and Senator Paul signed a pledge to protect tax breaks for companies that ship jobs overseas."

Paul told CNN's Wolf Blitzer that it is not yet clear if Gray will be a formidable opponent.

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