By Jeff Mason
CHICAGO (Reuters) - U.S. President Barack Obama congratulated Republican rival Mitt Romney on Tuesday for running a hard-fought race for the White House and expressed confidence he would win re-election during a stop at a local campaign office to thank volunteers.
"I ... want to say to Governor Romney congratulations on a spirited campaign. I know that his supporters are just as engaged and just as enthusiastic and working just as hard today," Obama said as volunteers made phone calls encouraging supporters to get to the polls.
"We feel confident we've got the votes to win, but it's going to depend ultimately on whether those votes turn out. And so I would encourage everybody on all sides just to make sure that you exercise this precious right that we have that people fought so hard for us to have."
Obama made calls to volunteers from the campaign office to thank them for working for his re-election.
"I expect that we'll have a good night, but no matter what happens, I just want to say how much I appreciate everybody who supported me, everybody who's worked so hard on my behalf," he said.
Opinion polls show Obama and Romney in a virtual dead heat, although the Democratic incumbent has a slight advantage in several vital swing states that could give him the 270 electoral votes needed to win the state-by-state contest.
Traditionally presidential candidates get media attention on Election Day by going to vote. But Obama cast his ballot in Chicago last month - part of his campaign's push to get its supporters to vote early.
So the president's visit to the office gave him a chance to get in front of the cameras, generate news coverage and encourage turnout.
Obama and Romney, a former Massachusetts governor and private equity executive, have fought a largely negative campaign. Obama's team attacked Romney for his business record, and Romney's team criticized the president for presiding over high unemployment and a slow economic recovery.
Obama's conciliatory comments represent the close of the bitter campaign and could appeal to last-minute undecided voters, who are turned off by the lack of bipartisanship in Washington.
In addition to his campaign office stop, Obama is doing a round of interviews and is expected to play basketball with friends, a tradition for the sports-loving president on Election Day.
(Editing by Xavier Briand)