NEW YORK, Oct 4 (Reuters) - Small- and mid-capitalization stocks climbed on Thursday, with coal shares jumping after comments by U.S. presidential candidate Mitt Romney in support of the coal industry.
Shares of Arch Coal gained 7.9 percent to $6.69 while shares of Alpha Natural Resources were up 6.8 percent at $6.73.
During Wednesday's debate with President Barack Obama, Romney, a Republican, said he would favor burning clean coal.
Energy shares bounced back with oil prices after the previous day's slide. Brent November crude rose $4.41, or 4.08 percent, to settle at $112.58 a barrel. Brent fell 3.1 percent on Wednesday.
Shares of Oil States International were up 3 percent at $77.36 and shares of Superior Energy Services were up 0.8 percent at $19.30.
The S&P MidCap 400 index gained 0.8 percent while the S&P SmallCap 600 index were up 0.6 percent. In comparison, the benchmark S&P 500 was up 0.7 percent.