Keller @ Large: Democrats Seek To Set Themselves Apart Before Crowded Primary Election

BOSTON (CBS) -- The ten Democrats seeking the party nomination to face Republican Rick Green in November for the Third Congressional District seat being vacated by Niki Tsongas have a common problem - how do you break through the clutter of such a large field?

For four of the Democrats, TV advertising is providing a forum for such a breakthrough. And after reviewing all of their most recent offerings, it's clear they share a common denominator - opposition to the president.

But beyond that, divergent strategies are on display.

Former Boston mayoral aide Dan Koh's ads are packed with video of young people, to underscore his pitch for generational change. "Every generation has its moment," he says in one spot. "That moment is now."

By contrast, an ad from former congressional aide Lori Trahan features seniors, traditionally a more reliable voter group. "I'll always stand up for working people, for seniors," she says.

Then there's this from former Ambassador Rufus Gifford: "Anyone who can look in the face of a gay kid who grew up in the eighties and tell them they haven't struggled in their life is fooling themselves." All these ads feature personal detail, but no one emphasizes it more than Gifford, who is seen in virtually every shot of his ads and features video of himself with his spouse.

And then there's state Senator Barbara L'Italien, who packs a little bit of everything into her only TV ad so far: a slap at Trump, a sequence boasting about her Beacon Hill experience, and a shot at the Archdiocese where she's seen attending a same-sex wedding and remarking: "[I] led the fight to pass marriage equality - that one got me kicked out of my church" as the minister conducting the ceremony frantically tries to wave her off.

There are six other candidates in the Democratic primary next Tuesday who have yet to run t-v ads: Jeff Ballinger, Alexandra Chandler, Beej Das, Leonard Golder, Bopha Malone and Juana Matias.

They all share a common problem - how to connect with voters on a tight budget and get them to turn out on this unusually-early primary day.