To stay nimble, marketing automation firm Silverpop just secured a fresh $25 million in funding. Escalate Capital Partners and Silicon Valley Ban led this most recent financing round.Founded as an email marketer back in 1999, Silverpop now applies behavioral automation to channels like social and mobile.For better or for worse, scaling targeted ad campaigns has never been more complex, according to Bill Nussey, CEO of Silverpop. Consumers are “no longer willing to be part of an audience or locked into a single channel,” he said.Showing its ability to adapt, Nussey said Silverpop increased new business by 40% from 2011 to 2012. That amounted to 380 new customers, last year -- one-third of which came to Silverpop for its marketing automation offerings, according to Nussey.Regarding 2012, Nussey said: “We dramatically stepped up our investment in sales and marketing.”Speaking to Silverpop’s future, a person close to the funding said: “Interestingly, the fund is venture debt, which … is often a bridge to an IPO, acquisition, etc. … Silverpop also opted for venture debt to avoid diluting equity.”Worldwide, Silverpop claims more than 5,000 brand clients.