The money race is under way in the 5th Congressional District. Hours after Elizabeth Esty reported raising $172,211 in just three weeks, Dan Roberti announced raising $255,900 in just 17 days.

“I’m humbled and honored by the support I received this quarter, and thankful to all those who contributed to my campaign,” Roberti said in an emailed announcement. “We have to hold Washington accountable to the people of Connecticut; this first fundraising hurdle was an important step towards that goal.”

Early money carries weight beyond what it can buy. It signifies credibility, and both Esty and Roberti are competing to convince Democrats that they are serious players in the race for a seat that will be left open by Chris Murphy’s pursuit of a Senate seat in 2012.

Each has some baggage. Esty is a former Cheshire council member and one-term state legislator who lost last year, admittedly in a Republican-leaning district. Roberti has no electoral background. Money helps convey seriousness of purpose.

And Roberti’s campaign suggested money may be more important than ever.

“In the wake of Citizens United, we can expect millions to flood into this race. To hold this seat, Democrats must raise the resources to compete and to win.” said Dan Kelly, a spokesman for Roberti’s campaign. “Dan is the one candidate, announced or prospective, that has shown that he can inspire donors to support his campaign.”

Perhaps. Roberti’s father is a wealthy, well-connected businessman. Esty and her husband, Dan Esty, the commissioner of environmental protection, presumably have a well-heeled circle of friends from their undergraduate days at Harvard and law school at Yale.

Democratic activists will be more interested to see if the money keeps coming in.