If you take a look at how Ronald Reagan voted while President, and his real track record in compromising with Democrats led by Tip O'neal, I believe he'd be called a RINO (or worse) in today's hyper partisan political climate.
Reagan knew that compromise, comity, and civility get things done in Congress. If we run people for Senate and the House who have poor qualifications, or are extremists who will never work with others in Congress, we will lose races.
If someone with Reagan's record were running for Senate today, I believe he'd be attacked for raising taxes, compromising with Democrats, and for his support for life of the mother abortion exceptions.
That is a sad statement about conservatives