U.S. Rep. Harold Ford Jr. (search) filed the federal paperwork Wednesday to become the second Democratic candidate in the 2006 U.S. Senate race.

"It's the first step in this process of presenting my case to represent the people of the state of Tennessee (search)," Ford told The Associated Press in a telephone interview from Washington.

"The biggest issues that the country will face will be heard and decided in the U.S. Senate," he said, naming energy reform, national security and education as his top issues.

The five-term Democratic congressman from Memphis has told voters for months that he was planning to run but hadn't said when he would officially enter the race.

The seat is currently held by Majority Leader Bill Frist (search), who has said he doesn't plan to seek a third term.

Ford filed the Federal Election Commission papers to begin raising money for the race Wednesday. He already has about $1.5 million in cash from his House campaign that can be redirected to his Senate bid.

State Sen. Rosalind Kurita is the only other declared candidate for the Democratic nomination. Republicans seeking their party's nomination are former U.S. Rep. Ed Bryant, former Chattanooga mayor Bob Corker and former gubernatorial candidate and congressman Van Hilleary.

Ford is 35 years old and single.