By Scott Malone
BOSTON (Reuters) - Veteran Representative Edward Markey of Massachusetts on Tuesday won the U.S. Senate seat vacated by John Kerry and helped Democrats maintain their majority in the chamber.
Markey, 66, claimed victory in a post on his official campaign Twitter page, saying: "Thank you Massachusetts! I am deeply honored for the opportunity to serve you in the United States Senate."
Local cable news station NECN said Markey secured 55 percent of the vote with 99 percent of districts reporting.
Markey, who has been vocal on climate issues, said he would push for more investment in alternative energy sources.
"I want to lead the effort to launch a clean energy revolution in our country," Markey told supporters in Boston. "We can combat climate change, break our dependence on imported oil and create jobs here in Massachusetts and across our country."
The win caps a campaign that Markey began in December, shortly after President Barack Obama said he wanted to appoint Kerry U.S. Secretary of State.
In a statement, Obama said Markey has "earned a reputation as an effective, creative legislator, willing to partner with colleagues across the aisle to make progress on the issues that matter most. The people of Massachusetts can be proud that they have another strong leader fighting for them in the Senate, and people across the country will benefit from Ed's talent and integrity."
Markey ran an aggressive campaign, painting Gomez, a private equity executive and former Navy SEAL, as out of touch with Massachusetts voters.
Gomez, the son of Colombian immigrants and a graduate of Harvard Business School, polled well among Republicans. But that support was not enough to win a majority of voters in the heavily liberal state.
Democrats also remembered the lessons of three years ago, when little-known Republican lawmaker Scott Brown won a special election to fill the late Democrat Edward Kennedy's U.S. Senate seat.
Obama and former President Bill Clinton traveled to Massachusetts this month to campaign for Markey, who lead in polls throughout the primary and general election campaigns.
Conceding defeat, Gomez told supporters: "In the military you learn one thing ... not every fight's a fair fight. We were massively overspent. ... But in the face of this great adversity we could not have fought a better fight."
Republican political strategist Eric Fehrnstrom said Gomez could be "a battle-tested GOP candidate for statewide office in 2014" when Massachusetts voters will choose a new governor.
Markey, who will have to defend his Senate seat in November 2014, was first elected to the House of Representatives in 1976.
Democrats have a 54-46 majority over Republicans in the U.S. Senate.
(Editing by Dina Kyriakidou, David Gregorio and Stacey Joyce)