By Andrew Osborn LONDON (Reuters) -Russian politicians on Wednesday savoured preliminary U.S. midterm election results which they cast as a humiliating and overdue blow to Democratic President Joe Biden, but the Kremlin said it expected no improvement in battered U.S.-Russia ties. The elections are being closely watched in Russia, which wants Washington to halt its rolling programme of generous military aid to Ukraine. Some pro-Kremlin Russians hope Republican success could mean Biden faces a tougher and longer slog to get military aid packages approved in future. Pro-Kremlin hawks also hope t…