Trailing Democratic challenger Mark Kelly in one of the country’s most hotly contested Senate races, Arizona Sen. Martha McSally is seeking to tie herself to an issue with across-the-aisle appeal: insurance protections for people with preexisting health conditions.“Of course I will always protect those with preexisting conditions. Always,” the Republican said in a TV ad released June 22.The ad comes in response to criticisms by Kelly, who has highlighted McSally’s votes to undo the Affordable Care Act. That, he argued, would leave Americans with medical conditions vulnerable to higher-priced i...