Mass. Senate hopefuls hit the campaign trail again

BRAINTREE, Mass. (AP) -- Republican U.S. Sen. Scott Brown and Democratic rival Elizabeth Warren are being joined by two former political rivals in the waning hours of Massachusetts' grueling U.S. Senate race.

Former Republican Gov. William Weld campaigned Sunday with Brown at Boston's Faneuil Hall, while Democratic Sen. John Kerry joined Warren at a campaign stop in Braintree.

Weld characterized the Brown and Warren race as a battle of "man versus machine," while Kerry said he needed Warren as a partner in the Senate to help push President Obama's agenda.

Weld and Kerry battled in another high-profile Senate race, which Weld lost to Kerry in 1996.

Both parties are keeping a close eye on the Massachusetts election as they fight for control of the Senate.

The race is the most expensive in state history.