Will the GOP Take Over the Senate?

Republican Senate candidates Scott Brown and Cory Gardner on Monday embraced the notion that climate change is caused in part by human activity, despite previously expressing skepticism that man-made climate change is real.

Brown, a former Massachusetts senator, is seeking to unseat Sen. Jeanne Shaheen in New Hampshire, while Gardner, a congressman from Colorado, is looking to defeat Sen. Mark Udall in that state. Both Senate races, regarded as unexpectedly competitive for Democrats, had debates on Monday -- the first for New Hampshire candidates, the second for Colorado. In both,...

There's one American voter with particularly high stakes in whether Republicans win control of the U.S. Senate on Election Night.

Meet Barack Obama.

Republicans wrestled control of the House from Democrats four years ago. Since then, President Obama has counted on the Democratic majority in the Senate to block the GOP's congressional agenda and make life a little easier for the White House.

Senate Democratic Leader Harry Reid has been able to do that because the Senate majority has the power to control the calendar, set the rules and decide...