Most election coverage has been focused on the race for the White House. But control of the U.S. Senate is also a top prize tomorrow.
Right now Democrats control 53 out of 100 seats, thanks to a couple of independent senators who caucus with them.
Republicans need to gain four seats to take control, and with more than a dozen races considered competitive Tuesday, that is a very real possibility.
In Virginia, Republican George Allen is neck-and-neck with Democrat Tim Kaine, fighting for a seat that's being left open by outgoing Democrat Sen. Jim Webb.
Wisconsin is another even race for an open Democrat seat. GOP candidate Tommy Thompson is giving the Democrat's Tammy Baldwin a run for the money.
In Arizona, a seat being vacated by retiring Republican Jon Kyl could go either way. GOP Rep. Jeff Flake is facing a tough fight with Democrat Richard Carmona.
In heavily Democratic Massachusetts, Republicans may lose a seat. Incumbent Sen. Scott Brown is losing in the polls to challenger Elizabeth Warren.
Despite his verbal gaffe early in the campaign, Republican Todd Akin also still has a good chance to claim a Democrat seat in Missouri from Sen. Claire McCaskill.
Other key Senate races to watch tomorrow include: Connecticut, Florida, Indiana, Maine, Michigan, Montana, Nebraska, Nevada, New Mexico, North Dakota, Ohio, Pennsylvania, and Texas.
**CBN News Political Editor John Waage predicts Republicans will take control of the Senate tomorrow. Click here for more of his Election Day predictions.