Sen. Rob Portman, R-Ohio, will not run for president in 2016, and instead plans to seek re-election to his Buckeye State Senate seat.
"With the new Republican majority, I see a real opportunity over the next two years to break the gridlock in Washington and actually get things done to help Ohioans and all Americans," Portman said in a statement Tuesday morning. "That's where I believe I can play the most constructive role."
Portman's official re-election announcement likely makes the seat harder for Democrats to pick up in 2016. With Democratic Sen. Mary L. Landrieu projected to lose re-election in this weekend's runoff against Rep. Bill Cassidy, Democrats will need to pick up five seats to reclaim control of the chamber.
First elected to the Senate in 2010, Portman found himself on the short list for vice president in 2012. GOP presidential nominee Mitt Romney ultimately selected Rep. Paul D. Ryan of Wisconsin, but Portman still played a role in the race by advising Romney on the campaign.
Since then, his name has surfaced as a potential presidential candidate in the crowded 2016 GOP primary field. In Ohio, candidates can run for president and their House or Senate seat at the same time, though Portman had previously said he would not seek both offices.
Ohio is a swing state in presidential years. President Barack Obama carried it in 2012 by a 2-point margin, making it a potential Senate pick-up opportunity for Democrats in 2016.
Portman's re-election announcement likely will make recruiting difficult for Democrats.
He is a prolific fundraiser, and starts the cycle with more than $5.5 million in cash on hand.
Though reliably conservative on many issues, he notably reversed his position on same-sex marriage in 2013 , supporting the cause after his son made public he is gay.
And the Democratic bench for statewide office in Ohio is thin.
Democrats are coming off of an embarrassing showing in the state's governor's race. Democratic nominee Edward FitzGerald lost to GOP Gov. John Kasich by a 31-point margin.
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