Larry J. Sabato's Crystal Ball » Bet on a Republican Senate Majority

While many races remain close, it’s just getting harder and harder to envision a plausible path for the Democrats to retain control of the Senate. Ultimately, with just a few days to go before the election, the safe bet would be on Republicans eventually taking control of the upper chamber. We say eventually because there’s a decent chance we won’t know who wins the Senate on Election Night. Louisiana is guaranteed to go to a runoff, and Georgia seems likelier than not to do the same. The Georgia runoff would be Jan. 6, 2015, three days after the 114th Congress is scheduled to open. Vote-counting in some states, like Alaska, will take days, and other races are close enough to trigger a recount

Source: Larry J. Sabato's Crystal Ball » Bet on a Republican Senate Majority