Money isn’t everything in politics. But it sure helps, especially in local races for open seats. Just ask Cambridge state representative Jarrett Barrios, who raised an estimated $400,000 and broke several records en route to his successful bid to win the Democratic nomination for the Senate seat given up by Senate president Tom Birmingham in his run for governor. Which means, of course, the seat is his.

With 80 percent of precincts reporting at press time and a 1500-vote lead over Cambridge city councilor Anthony Galluccio and Everett alderman Carlo DeMaria Jr., Barrios is poised to become the first Latino and the first openly gay candidate to win a seat in the Massachusetts Senate. Barrios’s prodigious fundraising total, when combined with the estimated $200,000 raised by Galluccio and the lesser amount raised by DeMaria, pushes the count for the entire campaign up into the $600,000 range, another likely record.

Barrios used his money to carpet-bomb voters in the district with a variety of direct-mail pieces — both positive and negative (most were about Galluccio) — in the weeks leading up to the primary, as well as for polling, a bevy of consultants, and a sophisticated get-out-the-vote (GOTV) effort on Primary Day. He also was helped indirectly in Chelsea and certain other sections of the district by an unprecedented GOTV initiative aimed at Hispanics and coordinated by żOiste?, the Massachusetts Latino Political Organization.

In other districts, money dominated as well. In West Roxbury’s race for the House seat given up by Representative David Donnelly, three-time candidate Michael Rush, a high-school history teacher, bested John Hickey and two other candidates in a four-way Democratic primary. Rush raised over $35,000 in his bid, slightly more than Hickey, a former legislative aide and manager at the Boston Water and Sewer Commission. Rush faces a Brookline Republican and an unenrolled challenger in November.

In South Boston, only former Big Dig liaison Bob O’Shea even bothered to file a campaign-finance report. Office of Campaign and Political Finance spokesman Denis Kennedy said that primary winner Brian Wallace — an author and former political operative for Boston mayor Ray Flynn — and Shawn Murphy, former Boston City Council staff director, failed to file pre-primary reports. Ten days prior to the primary, O’Shea had raised nearly $50,000. Sources say Wallace could double that amount after a series of fundraisers featuring early-1960s pop musicians Tavares and the CliffNotes. Kennedy said the tardy candidates face daily fines for failing to file their reports.

The exception to the money rule appears to be the 18th Suffolk House race, where incumbent state rep Brian P. Golden eked out a victory despite being outspent nearly two-to-one. Golden’s primary challenger, David Friedman — a well-heeled young attorney on leave from the downtown law firm of Hill & Barlow — raised nearly $100,000 in his bid against the two-term lawmaker. Friedman and Paul Felker, the third candidate, both benefited from anger among voters over Golden’s endorsement of George W. Bush in the 2000 presidential race. But Golden, with $50,000 in the bank, hung on — thanks in large part to low turnout among students and newcomers in the Allston/Brighton district.

Money, however, could not save four-term state rep Maryanne Lewis of Dedham. The top Finneran lieutenant was ousted in an upset bid by Dedham selectman Robert Coughlin. Lewis, who had raised over $133,000 by the reporting deadline, used a barrage of direct-mail and cable-television ads to try to hold off Coughlin, the scion of a popular Dedham political family. But Coughlin raised over $110,000 himself, and, thanks to a conservative old-boy network in the suburban community, he succeeded in defeating Lewis by an estimated 250 votes.