Steve Helber, AP
Republican vice presidential candidate Indiana Gov. Mike Pence, gestures as he addresses a rally in front of the Colonial Capitol in Williamsburg, Va., Tuesday, Sept. 20, 2016.

Some Republicans who dislike Donald Trump are attempting various mental gymnastics to justify a decision to vote for Trump. One of those is the claim that they really are voting for Mike Pence, Trump’s vice presidential running mate. Even Gov. Gary Herbert has said that he is voting for Pence, and Trump “comes along with the package.” Of course, such talk is nonsensical.

Voters today do not vote for the vice president. There was a time in American political history when a vice presidential candidate would bring along his or her own state. In those cases, a vice presidential running mate who appealed to a certain geographical area that was not keen on the presidential candidate might help carry the ticket in his own state. For example, Richard Nixon helped Dwight Eisenhower win California in 1952, after the state had gone Democratic for five previous elections. Eight years later, Lyndon Johnson joined John F. Kennedy’s ticket in 1960 and helped Kennedy win Texas.

However, these cases show how anyone who voted for the president to put the running mate in power was sadly mistaken. Eisenhower ignored Nixon over the next eight years. He gave him little to do and kept him out of the loop. Similarly, while Johnson was vice president, he was consigned to cutting ribbons at formal ceremonies and attending funerals of foreign leaders. Kennedy offered him no decision-making role. Only when Kennedy was assassinated did Johnson gain power. But no one should expect, or wish for, such a tragedy when they are voting for a presidential ticket.

One instance where the nation should have looked more seriously at the second person on the ticket was 1944, when Franklin Roosevelt ran for his fourth term while seriously ill. Within six months of winning that term, Roosevelt died. Harry Truman, vice president for three months, became president while the nation was still at war.

The cases of Donald Trump and Hillary Clinton do not match, even closely, that of Franklin Roosevelt. Hiding a major illness today, as Roosevelt’s administration did in 1944, is extremely difficult to do. Trump’s weight problem and Clinton’s pneumonia pale in comparison to Roosevelt’s case.

The power of the vice president compared to that of the president is like that of a lawn mower compared to a jet. Whatever power the vice president has, beyond the constitutional role of presiding over the Senate (which vice presidents rarely do), is almost completely dependent on the president. Presidents give vice presidents particular tasks to keep them busy. For example, Joe Biden was granted power over the implementation of the 2009 economic stimulus package. Al Gore took on a government reform portfolio, while George H.W. Bush supervised the drug war. But all of those responsibilities were grants from the president. In fact, the president can choose to give the vice president nothing to do, as Eisenhower and Kennedy did to their vice presidents.

An informal tradition has developed that the vice president meets periodically with the president and gives his counsel in private. The extent to which the president actually takes it is difficult to know. However, one of the most influential recent vice presidents, Dick Cheney, once expressed frustration over George W. Bush’s failure to do what Cheney suggested. That statement reminds us how powerful the president is, and how dependent the vice president really is.

A wise president will choose a vice president who can help with governance, and then listen to that individual. That is particularly true when a president is an outsider to Washington and the federal government (which seems to be a common career path for presidents nowadays). Barack Obama chose Joe Biden because he brought 36 years of experience in the U.S. Senate. Similarly, Bill Clinton’s selection of Al Gore gave him someone who had served in both the U.S. House and the Senate prior to becoming vice president.

But there is no guarantee that Mike Pence will be accorded even that kind of hearing. Donald Trump could, and quite likely would, run the country how he feels it should be run and not how Pence would like to run it. A vote for Donald Trump is a vote for Donald Trump. Voters who pretend otherwise are deceiving themselves.

Richard Davis is a professor of political science at Brigham Young University. He is the author of "The Liberal Soul: Applying the Gospel of Jesus Christ in Politics." His opinions do not necessarily reflect those of BYU.