(CNN) -- Tuesday's off-year election may not have had the high stakes of the 2008 presidential election, but several races are significant on the national level:
• New York's 23rd Congressional District: Owens to win vacant U.S. House seat, CNN projects
Democratic candidate Bill Owens will be elected to a vacant U.S. House seat in upstate New York.
The race garnered national attention as local Republican leaders picked Dede Scozzafava because of her appeal to centrist Republicans, independents and even some Democrats. However, the decision sparked a revolt among conservative activists in the GOP.
Conservative Party candidate Doug Hoffman outpolled Scozzafava, forcing her to withdraw. Scozzafava has since endorsed Owens.
• Virginia governor: McDonnell is projected winner
CNN has projected that Republican Bob McDonnell will be elected Virginia governor. The 55-year-old former state attorney general will be the first Republican to win the state's highest office in 12 years.
With 99 percent of precincts reporting, McDonnell was leading Democratic opponent Creigh Deeds 59 percent to 41 percent.
The race was seen as an early referendum on voters' attitudes toward President Obama and his policies and an opportunity for Republicans to turn back recent Democratic gains.
• New Jersey governor: GOP's Christie is winner, CNN projects
Republican challenger Chris Christie will defeat New Jersey Gov. John Corzine, CNN has projected.
With 99 percent of precincts reporting, Christie was leading Corzine, a Democrat, 49 percent to 45 percent. Chris Daggett, an independent candidate, had 6 percent.
Corzine, who was seeking a second term, trailed Christie during the summer, but recent polls showed them in a dead heat. As Election Day approached, some thought growing support for the moderate Daggett might siphon votes from Christie.
• New York mayor: Bloomberg to win third term, CNN projects
New York City Mayor Michael Bloomberg will win a third term despite a tough challenge from Democrat Bill Thompson, CNN has projected.
With 99 percent of precincts reporting, Bloomberg led Thompson 51 percent to 46 percent.
Bloomberg's apparent victory comes after he changed the city's constitution to lift a two-term limit.
Bloomberg, an independent candidate, had led Thompson, the city comptroller, by double digits in most pre-election surveys. Bloomberg has outspent his rival in TV ads by $33 million to $2.66 million.
• Boston, Massachusetts, mayor: Menino wins, Globe says
Boston Mayor Thomas Menino has won a record fifth term, the Boston Globe reported. CNN is not making a projection in the race.
With all precincts reporting, Menino led City Councilman Michael Flaherty 57 percent to 42 percent, according to the Globe.
In Menino's previous races, he either won overwhelmingly or ran unopposed.
• Houston, Texas, mayor: Heading for runoff
City Controller Annise Parker and former City Attorney Gene Locke are headed for a runoff.
Parker ended up with 30.5 percent of the votes and Locke received 25.9 percent of the total, the Houston Chronicle reported. If Parker wins the runoff, she would be the city's first openly gay mayor.
• Atlanta, Georgia, mayor: Two appear set for runoff
A runoff appears necessary to determine whether 35 years of African-American control of the mayor's office will end in Georgia's capital city.
With 100 percent of precincts reporting in Tuesday's election, City Councilwoman Mary Norwood, who is white, had 45 percent of the vote, compared with 37 percent for her nearest challenger, former state lawmaker Kasim Reed, who is black, according to the Atlanta Journal-Constitution.
A candidate needs more than 50 percent of the vote to win. With no one receiving that percentage, the top two finishers will go to a runoff. Incumbent Shirley Franklin, limited to two terms, said before Tuesday's race that she would vote for Reed.
• Maine same-sex marriage vote: Same-sex marriage repealed
Maine voters repealed the state's same-sex law, according to the Bangor Daily News.
With 87 percent of precincts reporting, nearly 53 percent of voters chose to reject the law, with more than 47 percent voting to retain it, according to the Daily News.
When Gov. John Baldacci signed the legislation on May 6, he did so knowing there was a possibility that voters could overturn it. In September, opposition groups delivered the necessary signatures to get a vote.
• Medical marijuana in Maine: 'Yes' has lead
Early results seemed to favor the passage of a measure that would expand the use of medical marijuana in Maine.
With 87 percent of precincts reporting, 59 percent of voters chose "yes" in the referendum, according to the Bangor Daily News.
Voters in Maine, one of 14 states to allow the use of medical marijuana, were asked to decide whether to expand the list of conditions that could be treated with medical marijuana and make it easier to expand the list further. It also would create state-licensed dispensaries.
• Expanded gay rights in Washington state: 'Yes' has slim lead
Late Tuesday night, voters were approving what is called Washington's "everything but marriage" bill by 51 percent to 49 percent, with about 50 percent of the vote counted, CNN affiliate KXLY reported.
The bill was signed into law earlier this year and gave registered domestic partners additional state-granted rights currently given only to married couples.
CNN's Paul Steinhauser, Emily Sherman, Ed Hornick, Robert Yoon and John Helton contributed to this report.