Support for legal abortion in the U.S. has hit its highest point in two years, according to an Associated Press-GfK poll. The survey shows an increase in backing among Americans in both major political parties over the last year. The poll was conducted in the weeks after three people were slain in a November shooting at a Planned Parenthood clinic in Colorado. Of those surveyed, 58 percent said they believe abortion should be legal in all or most cases, up from 51 percent in an early 2015 poll. Republicans remain deeply divided on the issue, with seven in 10 conservative Republicans telling pollsters abortion should be illegal in most or all cases.