The pledge is widely viewed as an effort to convince Trump not to run as a third-party candidate, a move which could strip away potential GOP voters.
Trump’s dictatorial, nativist, crony-capitalist fearmongering may push conservatives in a less liberty-loving direction.
His take on issues like the Iran nuclear deal is more realistic than others.
In fact, a handful of other contests may determine the Republican presidential nominee.
Univision's Jorge Ramos was escorted out of a Donald Trump news conference in Iowa on Tuesday night.
Even Common Core champion Bush pushes local solutions.
The GOP presidential candidate recently said there's "nothing that can't be done without fetal tissue."
Most GOP candidates promise brave new interventions and wars.
Some Republicans are challenging their leaders to close down the government if Planned Parenthood is not defunded.
Will the rightward tilt of the GOP prevent it from winning the White House and governing effectively?
What the GOP candidates said about replacing Obamacare shows a woeful lack of knowledge and expertise.
After last week's primary debate, poll shows 23 percent of Republican voters support Donald Trump.
Presidential primaries are minefields for the incautious. And Trump is not a cautious man.
The top 10 Republican candidates in the polls will participate in the Thursday night debate on Fox.
The legislation received 53 out of 60 needed votes, with 46 voting against.
His lawyer and spokesman, Michael Cohen, said it is legal for a husband to rape his wife.
The Republican presidential contender says he "absolutely" will consider a third-party run if RNC isn't supportive.
Kasich touts gubernatorial, congressional experience.