By Nandita Bose WASHINGTON (Reuters) – Some senior White House officials have been second-guessing their messaging to voters around abortion in recent weeks, sources familiar with the matter said, as forecasts turned in Republicans’ favor in the run up to the midterm elections. Many Democrats are no longer optimistic about retaining one or both houses of Congress in Tuesday’s midterms, and some have asked if party leaders and the Joe Biden White House should have spent more time talking about the U.S. economy, and less about women’s reproductive rights. Inflation is the top voter concern, damp…