U.S. healthcare shares pick up steam as some political worries abate

NEW YORK (Reuters) - U.S. healthcare stocks, led by health insurers, have gained strength in recent weeks, buoyed by solid third-quarter earnings and investor comfort that political risks to the sector have eased. Wednesday's Democratic presidential debate could test their momentum.The S&P 500 healthcare sector has climbed 11% since hitting a recent low on Oct. 2, outperforming an 8% rise for the overall benchmark S&P 500 over that time.Still, healthcare remains a stark underperformer so far..