They could toss it of course, but I think some of the far left Dem loonys like Kucinich may try to use it to make their arguments for passing European style gun laws seem a little less radical. I don't expect any Pub candidate to answer any of the questions, but I believe Rooty would like to see more restrictive gun laws passed even though he can't say so if he hopes to win the GOP nomination. He has been an outspoken opponent of gun owners and 2nd Amendment rights ever since he was a hotshot NY prosecutor, and I can't believe he could truthfully change his stripes now even if he knew it would improve his status with pro-gun voters in the GOP nomination race.
I don't trust Mitt on the issue either, but I don't think he would put passing more gun control laws on his to-do list if he became president. AFAIK all the other Pub candidates at least give lip service to the RKBA, but who knows what their real beliefs are on the issue. The only two who I fully believe in on the issue are Hunter and Fred, and the outlook isn't very promising now for either one. McCain used to be very good on the issue, but right after the Columbine tragedy he campaigned through several western states for stricter state gun control laws so I don't think his heart is really in it when he claims to support the RKBA.
The Supreme Court is going to rule on the 2nd Amendment before the political conventions take place next summer. Giuliani has stated that he agrees with the reasoning of the DC Court in the case that is on appeal. That’s the right position to take, in case there’s any confusion.
Even if he disagreed with it, this court decision is going to trump everything, including even a possible Hillary presidency.