Former Sen. John E. Sununu, R-N.H., will not challenge Democratic Sen. Jeanne Shaheen to a rematch, he told the  the New Hampshire Union Leader in an interview Friday.

His announcement opens the floodgates for Granite State Republicans looking at the race. Many potential GOP candidates were waiting for Sununu to make a decision about the race before announcing their intentions.

CQ Roll Call recently reported that former Reps. Jeb Bradley and Frank Guinta are looking at the race. Former Sen. Scott P. Brown, R-Mass., refused to rule out a run for New Hampshire Senate last week.

Shaheen is in a strong position for re-election, but New Hampshire remains a competitive state. On Thursday, she told the Union Leader that she had raised $1.23 million in the first quarter of this year and has $1.46 million in cash on hand.

Sununu cited wanting to spend time with his family as one of his reasons not to run in 2014.