Microsoft is trying to persuade politicians to take out targeted ads on Xbox Live, Skype, MSN and other company platforms as midterm elections begin heating up around the country. To plug the idea, Microsoft officials handed out promotional materials Thursday at CPAC, the annual conference for conservatives. It’s the latest move by tech companies to seize a piece of the lucrative political ad market. The ads, which would appear on the Xbox Live dashboard and other Microsoft products, combine Microsoft user IDs and other public data to build a profile of Xbox users. Campaigns can then blast ads to selected demographic categories, or to specific congressional districts. And if the campaign brings its own list of voter e-mail addresses, Microsoft can match the additional data with individual customer accounts for even more accurate voter targeting.