Former Democratic Rep. Joe Sestak of Pennsylvania said he would pass on a race for governor in 2014 and instead seek a rematch with Republican Sen. Pat Toomey in 2016.
Sestak made the announcement in an email to supporters on Tuesday, saying he's launching an exploratory committee for a Senate bid against Toomey.
The announcement came as something of a surprise, since Sestak had raised more than $460,000 for his personal political action committee and polls showed him leading the field of Democratic gubernatorial contenders.
In 2010, Sestak lost a cliff-hanger of a Senate bout to Toomey, who finally eked out a win by about 2 percent of the vote.
Toomey's popularity has jumped after his co-sponsorship of a background-check bill for gun owners along with Democratic Sen. Joe Manchin of West Virginia. A Quinnipiac poll last month found Toomey's approval rating at 48 percent, a five percentage point increase from the previous month.
John Gizzi is chief political correspondent and White House correspondent for Newsmax.