Most of the leading 2016 presidential candidates have weighed in on the hot-button issue of immigration this campaign season; however, their opinions vary widely on how and if the country needs to build a wall to secure its border.

Leading Republican candidate Donald Trump has perhaps been the most vociferous on the issue, insisting he would not only erect a wall along a 2,000-mile stretch of land, but he would force Mexico to foot the bill for its construction.

Many of his rivals have branded his pledge as impractical and unrealistic. Still, Trump continues to boast on his website, "There must be a wall across our southern border," The Associated Press reports.

In addition, during an October GOP debate, he referenced the Great Wall of China in promoting his idea. He also reiterated his claim, "Mexico is going to pay for the wall."

Previously, Trump boasted, if elected, he would move to deport some 11 million immigrants in less than two years.

Texas Sen. Ted Cruz has been almost as adamant as Trump in his support for a wall, but not nearly as forceful. On his website, Cruz pledges his support for the idea, though he offers no specifics on how he would make that happen.

While insisting no candidate is better prepared than he is to tackle the issue of immigration, Florida Sen. Marco Rubio has also been vague about supplying details of a plan.

During the Republican debate in September, in response to a related question, he said, "We must secure our border, the physical border, with a wall, absolutely."

One-time leading Republican candidate, former Florida Gov. Jeb Bush separated himself from the crowded GOP field by asserting he finds it unnecessary to build a massive border fence.

"We don't need to build a wall," he recently told a group of Latino business owners. He added Trump's wall strategy is "not based in reality."

On the Democratic side, Hillary Clinton recently told supporters gathered at a New Hampshire town hall, "I voted numerous times when I was a senator to spend money to build a barrier to try to prevent illegal immigrants from coming in."

She later apologized for her use of the term "illegal immigrants" and, as of late, has not indicated whether she still supports the idea.

Vermont Sen. Bernie Sanders couldn't be clearer about where he stands on the matter.

While stressing he understands the importance of securing the border, Sanders recently shared on his website he opposes building a fence to do so.