That's bullshyt because if it were true, then the Democrats would be offering GOOD arguments and just losing anyway. But that's not what's happening. OP is pointing out that the Dems as often as not are offering for-shyt arguments. For example, look at your argument.
* "It's that they're religious! Their religion is to blame!"
* "We're the logical ones but they're religious!"
* "Religious idiocy!"
* "Old pieces of shyt"
You didn't offer any of your own logic, just attacked religion. It ain't getting you anywhere.
Nor are Democrats on this issue.
Peter Singer of Princeton is an atheist and one of the most renowned bioethicists in the country. He's argued strongly that there's no scientifically-grounded moral line between late-term abortion and infantcide, and that in fact it is difficult to draw a clear-cut moral line anywhere in the development of the fetus. The problem is that at some point a baby is a baby in every single way except for the fact that there's an umbilical cord still attached, and it is extremely difficult to say something has no right to live due to the mere fact of a potentially removable feeding tube.
Strong liberal arguments on abortion should take into account nuance, compassion, the acknowledgement of scientific uncertainty regarding the beginning of personhood, and likely compromise. But we don't get that. So for all intensive purposes conservatives are currently winning the abortion debate and likely will continue to win most of the battles in the near future.