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Sanders trying to make the most of his booming 2016 crowds

In this July 6,2015, photo, Democratic presidential candidate Sen. Bernie Sanders, I-Vt., speaks at a campaign rally in Portland, Maine. Sanders is packing 'em in: 10,000 people in Madison, Wisconsin. More than 2,500 in Council Bluffs, Iowa. Another 7,500 this week in Portland. The trick for the independent senator from Vermont is to turn all that excitement into something more than a summer fling.( (AP Photo/Robert F. Bukaty) In this July 6,2015, photo, Democratic presidential candidate Sen. Bernie Sanders, I-Vt., speaks at a campaign rally in Portland, Maine. Sanders is packing 'em in: 10,000 people in Madison, Wisconsin. More than 2,500 in Council Bluffs, Iowa. Another 7,500 this week in Portland. The trick for the independent senator from Vermont is to turn all that excitement into something more than a summer fling.( (AP Photo/Robert F. Bukaty)

By Associated Press July 8, 2015 1 min read

PORTLAND, Maine (AP) – Democratic presidential candidate Bernie Sanders can sure pack ’em in. He recently drew a crowd of 10,000 in Madison, Wisconsin, and another 7,500 this week in Portland, Maine.

But for Sanders to turn his insurgent campaign into a viable challenge against unquestioned front-runner Hillary Rodham Clinton, he will need to covert those willing to come hear him speak in the summer of 2015 into volunteers, donors and voters in 2016.

And for all the crowds that Sanders is attracting, he remains far behind Clinton in the work of building a campaign organization.

Right now, Sanders has a little more than 50 paid staffers in all. Clinton has nearly 50 in Iowa alone, as well as at least one in all 50 states.