Republican candidates fall behind in four pivotal Senate races

Republican Senate candidates are trailing further behind their Democratic rivals in four key swing states, according to a poll. A Cook Political Report/GS Strategy Group/BSG Swing State Project survey shows that Democratic Senate hopefuls running in Arizona, Michigan, Nevada and Pennsylvania have increased their vote share over their Republican challengers compared to a previous survey in May. The only state where a Republican candidate has improved their vote share from the previous survey is Wisconsin, where Republican Eric Hovde has gone from being 12 points behind Democratic Senator Tammy Baldwin...