Updated 3:20 p.m.A major anti-abortion group on Thursday announced its endorsement of Rep. Todd Tiahrt (R) over Rep. Jerry Moran (R) in the Kansas Senate primary.Kansans for Life held two press conferences in the state to announce that its political action committee is endorsing Tiahrt, according to one of his aides.Tiahrt and Moran are the only major Republican candidates running to succeed Sen. Sam Brownback (R), a darling of social conservatives and the anti-abortion movement who is stepping down to run for governor in 2010. Because both Members have similar voting records, the Kansans for Life endorsement could be a major boost for Tiahrt in the GOP primary. The winner of the nominating contest will be heavily favored to win the seat in November 2010. The announcement comes almost one month after well-known late-term abortion provider George Tiller was shot and killed during a church service in Wichita, where he practiced. Meanwhile, Moran was touting the official endorsement of Sen. John Thune (R-S.D.) on Thursday. Thune’s endorsement was not a surprise, as he had said earlier this year that he had promised his support to Moran last year. Thune, who was just elected GOP Policy Committee chairman, was one of several Senators who headlined a February fundraiser for Moran.Sens. Tom Coburn (R-Okla.) and Mike Johanns (R-Neb.) are also supporting Moran over Tiahrt. “Now, when the stakes are so high for our country, Jerry Moran’s principled leadership and conservative voice are needed in the U.S. Senate,— Thune said in a statement. “Jerry will bring a much-needed vote of common sense for fiscal responsibility, fighting terrorism and deciding the future of our judiciary.—