Microsoft launched a public-relations campaign for replacing state Route 520 bridge -- the frequently clogged regional artery used every day by thousands of its employees to make the trip across Lake Washington, from Seattle to Redmond and back. The company's campaign, which includes a website and a full-page ad (pictured) in Seattle Times, opposes an alternative proposal -- backed by new Seattle Mayor Mike McGinn and other public officials -- for a six-lane bridge with dedicated lanes for buses and light rail. The current plan calls for a six-lane bridge with two dedicated HOV lanes. Gov. Chris Gregoire has said that changing the plan now would set the project back by as many as 18 to 24 months. Microsoft general counsel Brad Smith spoke with reporters this morning about the company's campaign to move forward with the state's existing plan to replace the 520 bridge between Redmond and Seattle.