NASHVILLE (AP) — While Gov. Bill Haslam is keeping the door open to an expansion of the public pre-kindergarten program in Tennessee, any such move would remain a tough sell among some fellow Republicans in the Legislature.Haslam stressed that a federal notice that Tennessee intends to apply for a share of federal money available for pre-K expansion doesn’t mean the state will necessarily follow through. The governor said he is still awaiting the results of a multi-year Vanderbilt study on the effectiveness of the program before making up his mind.Tennessee could qualify for up to $17.5 million per year under the competitive grant federal grant program that is required to decide on disbursing the money to the states by the end of the year.Should Haslam ultimately decide to pursue more money for pre-K, he will have to persuade Republican Senate Speaker Ron Ramsey, a longtime critic of the program for 4-year olds.