Why John McCain would support Donald Trump as the GOP nominee

John McCain, the 2008 Republican presidential nominee and Arizona senator, said he plans to endorse his party's nominee for president in 2016, even if it's Donald Trump.

"I'm a loyal Republican," McCain said in an interview with CBS News Chief White House Correspondent Major Garrett. "I believe the best way to shape the agenda of the next president of the United States is to be part of the team and make my influence felt as strongly as possible."

"For me to walk away from the party of Abraham Lincoln and Ronald Reagan would be I think an abrogation of my responsibilities to the voters," he added.

Garrett asked McCain whether Trump, the businessman who has a substantial lead over the other 2016 candidates in national polls, represents the same party as his two predecessors McCain named.

After a pause, McCain responded, "I think he wants to."

"I disagree with him on a number of the statements and positions that he's taken, obviously. But if that's the verdict of the Republican Party and the majority of Americans, then I will do everything I can to help that president whether it be Trump or whoever because we are in a state of crises the likes of which we have not seen."

He said he believes he can bring "advice and counsel" to the next president because of his experience.

McCain said that Trump taps into "anger" and "frustration" among the electorate, especially among voters who haven't seen significant improvements in their lives. Those voters, he said, believe Republicans leaders in Washington have contributed to the gridlock, but he argued that's only valid to a degree.

He pointed to the bills that have passed recently, including a federal education overhaul, a budget deal and defense authorization bill. Plus, he said, the Republicans in the House and Senate finally put a bill to repeal Obamacare on the President Obama's desk.

"It takes a while to turn around people's views. But Americans are frustrated and here's a person who says he's going to make America great again. Here's a person on the other side that's giving Hillary Clinton a much bigger fight than we ever anticipated that's saying take out Wall Street. They're the bad people. I mean, that strikes a chord with Americans as well," he said, referring to Sen. Bernie Sanders, I-Vermont, who is challenging Clinton for the Democratic nomination.