TALLAHASSEE, Fla. (AP) – Republican Congressman Connie Mack IV will announce soon that he’ll seek the Senate seat once held by his father after earlier this year saying he would instead run for re-election, according to a spokesman.

Mack seriously considered entering the race until February, when he said a Senate run would take too much time away from his family. But the candidate he endorsed, Senate President Mike Haridopolos, dropped out and none of the remaining field has caught fire with Republican voters. The winner of the Republican primary will face Democratic Sen. Bill Nelson, who is seeking his third term.

“He will be entering the race,” said David James, a political spokesman. “Right now he’s making calls, talking to supporters, friends, grassroots activist, assembling a team.”

James said Mack will officially enter the race in the coming weeks. Mack has nearly $350,000 in his re-election account that he can use for a Senate race.

Mack served in the Florida House from 2000 to 2003, representing the Fort Lauderdale area. He moved back to Fort Myers to run for Congress, winning his seat in 2004. He also considered running for Senate during the 2010 election cycle, but instead said he would back then Gov. Charlie Crist in the race.

Like most Republicans, he took back his support and endorsed Marco Rubio when Crist decided to leave the Republican Party and run as an independent. Rubio won the election.

Mack is married to California Congresswoman Mary Bono Mack. He has two children and two stepchildren.

“Sometimes you have to put your family and friends above political ambition, but that doesn’t mean I’m going to shy away from the political fight in ‘012. I will continue to be a voice, I will continue to hold Sen. Nelson’s feet to the fire,” Mack said in February. “You can’t go to Washington and be one of the most liberal senators in Washington and then come back to Florida and claim that he is a moderate.”

Nelson won his seat in 2000 when Mack’s father, Connie Mack III, retired.

Before his February announcement, Mack showed signs he might entering the race. He attacked Nelson frequently in political emails, and his campaign website prominently featured a video of Nelson with President Barack Obama. The video criticized Nelson for being too liberal.

Other Republicans seeking the seat include former state Rep. Adam Hasner, retired Army Col. Mike McCalister, former steakhouse chain CEO Craig Miller and former Sen. George LeMieux, who served the last 16 months of Sen. Mel Martinez’ term.

A Quinnipiac University poll last month showed that 58 percent of Republicans were undecided and LeMieux leading the field with only 17 percent support, followed by McCalister with 11 percent and Hasner and Miller with 5 percent each.