The proposed Downtown Streetcar Project has been expanded to include the Ohio State University (OSU) campus in the first phase, according to Mayor Michael B. Coleman, while planned routes to German Village and the Brewery District would be held for a later stage.  The current version of the base line, developed by a 42-member committee of civic leaders known as the Downtown Streetcar Project Working Group, would run 2.9 mi. (4.7 km) along High Street from Mound Street to Buttles Avenue.  The OSU extension would add another 3.6 mi. (5.8 km).  The estimated capital cost for both segments ranges from $160.2 million to $192.1 million.  A spokesman for Coleman said the plan is still in a very preliminary stage and that the primary focus is on finding money to build it; the mayor has already said he won’t support a tax increase.