This is called "begging the question."

You're stating as fact in your question what you have not established with evidence.

There certainly is a vocal bit of Christianity - the evangelical ones - who tend to be politically conservative. See the Southern Baptists, e.g.

There are others who claim the Christian faith who definitely skew "progressive," socially. See the PCUSA, the UMC, and the UCC, e.g.

This also depends much on what you define as "progressive." Some claim that Christ was socialist since He advocated for acts such as feeding and clothing the poor.

What is missing is His command for government to be the means to do so. There are large bits of the Christian Scripture that expects the _individual and/or the church to do those things.

Is this progressive? Depends on who you ask, I suppose.

The largest church in my city (approx. 10,000) is decidedly "progressive," socially - its pastor was part of an advisory team to Obama before he ran for President, but it also acts as Christ commanded, loving others through action. It feeds children, provides free clothing, has a free dental clinic and medical clinic, and I even helped do free oil changes for single mothers and low-income families at this church.

The issue simply isn't as black and white as some media (such as reddit, e.g.) would have you believe.