BOSTON (AP) — Republican U.S. Sen. Scott Brown and Democratic challenger Elizabeth Warren are back on the campaign trail as the hotly-contested race heads into the homestretch.

Warren will be joined on Friday and Saturday by Democratic Sen. Al Franken of Minnesota. According to Warren’s campaign, the two will be joined by Rep. Edward Markey and other Democrats at an event in Lexington to discuss clean energy.

Franken is also scheduled to attend rallies for Warren on Friday in Cambridge and Worcester on Friday. He has appearances scheduled in Springfield and Southbridge on Saturday.

Brown’s campaign has not yet released his Friday schedule. The senator campaigned Thursday in Worcester, where he received the endorsement of the former head of the Teamsters local.

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