(Bloomberg) Labour Party Leader Keir Starmer has a mountain to climb to guide the UK opposition to victory in the next general election, facing double the challenge that confronted Tony Blair ahead of the 1997 landslide.Most Read from BloombergIsrael Latest: Scores of Civilians, Soldiers Kidnapped by HamasHamas Attack Prompts Blame Around Israeli IntelligenceBiden Says Israel Under Terrorist Attack, Pledges US SupportShock Incursion on Weakened Israel Imperils Regional GeopoliticsHamas Just T