Democrats are leading by double digits in Senate races in Nevada and Arizona, two battleground states that could be key to control of the upper chamber, according to new polls from Fox News. Rep. Ruben Gallego, the Democratic Senate nominee in Arizona, is leading Republican candidate Kari Lake by 15 points, according to the poll. In Nevada, Sen. Jacky Rosen, the incumbent Democrat, is leading Republican Sam Brown by 14 points. While the Democrats in Arizona and Nevada have opened significant gaps in their races, others in the party are still seen as being vulnerable in November, notably Sen. Jon...