ABC's Z. Byron Wolf reports: With perfect attendance and the help from Massachusetts moderate Scott Brown, Democrats broke a Republican filibuster in the Senate and moved one step closer to passing a slate of sweeping Wall Street reforms. Democrats fell short in a procedural cloture motion Wednesday when two of their own – Sens. Russ Feingold of Wisconsin and Maria Cantwell of Washington – voted with Republicans to continue debating the bill, which has been on the Senate floor for more than three weeks. Brown, who voted with his party on Wednesday, switched to vote with Democrats Thursday after receiving assurances from Democratic leaders that certain businesses will be exempted from new investment restrictions for banks. “Senator Brown could not support cloture yesterday because the bill did not address his concerns regarding the Volcker rule for both insurance companies and our safe custody banks – institutions that did not contribute to the financial crisis, but would be crippled by the current legislation and in turn would result in job losses,” a Brown spokesman said in a written statement. The two moderate Republican Senators from Maine voted with Democrats on Wednesday and Thursday.