U.S. Senator Susan Collins of Maine, a moderate Republican who helped block her party’s efforts to repeal Obamacare this year, plans to reveal on Friday whether she will keep her focus on Washington or make a run for governor next year. The four-term incumbent for weeks has been flirting publicly with the idea of launching a bid to succeed Governor Paul LePage, a fiery conservative who was first elected in 2010 on a wave of Tea Party support.