In the hotly contested U.S. Senate race, Sen. Scott Brown and challenger Elizabeth Warren are treating their national conventions in entirely different ways.

 While Brown declined an invitation to speak on national television, Warren seized the opportunity and landed on the schedule for Sept. 5.

Mo Cunningham, a political science professor at UMass Boston, said Brown needed to distance himself from the national GOP, which is seen as far too conservative for Massachusetts:

"The national Republican Party is just a weight around Scott Brown’s neck," Cunningham said. "He needs to run as far away from the national Republican Party as he can get.”

On the other hand, Warren sees a benefit in associating herself with President Barack Obama, who has a big lead in Massachusetts polls over Mitt Romney.

Cunningham said Warren's strategy is strikingly different than Brown's:"He is trying to run away from his national party and yet getting endorsements from some Democrats and she is willing to embrace her national party."

So who's more effective: Brown or Warren?
Warren is slightly behind Brown in public opinion polls in Massachusetts. But the race is very close. 

A survey by Public Policy Polling in mid-August had Warren behind by five points and trailing among independents.

Cunningham believes that both candidates need to appeal to independent voters. But they have two distinct paths to victory: Warren, he said, has the advantage of a larger partisan base and Obama at the top of the ticket. Brown needs Obama voters to split their ballots.