The millions of dollars spent by Mitt Romney’s allies on TV ads attacking his two main rivals have helped Mr. Romney pull ahead in the Republican presidential race. The resulting bitterness, however, is making it hard for him to lock down the nomination and end the party fighting that delights Democrats.
Republican insiders say Rick Santorum and Newt Gingrich are fuming over the hard-hitting 30-second spots that sent them tumbling after they gained early leads in Iowa, Florida, Michigan and other states.
Every election bruises some feelings, but campaign veterans say Mr. Santorum and Mr. Gingrich feel the commercials were pointedly unfair. That’s a big reason they keep fighting despite Mr. Romney’s significant lead in delegates and pleas from some Republican leaders to close ranks and focus on President Obama.
“The Romney folks have run a pretty ugly campaign,” said Mike McKenna, a Republican strategist and pollster who is unaffiliated in the presidential race. “It’s been very personal; it’s been very ugly; it’s been very hostile. There’s a lot of bad blood.”