Not a pro, but I'd paint it over. Just because it's holding the load, and it's too much work to replace it. Those little cracks are no big deal, you can seal the cracks, Home Depot sells wood sealer. If you paint it every the other year, it will last for a long time.

Thanks both for your feedback.

Summers is correct. The only reason to replace it at this point would be if (in the first picture) the wood had termite damage and was soft and spongy like a cork in the areas where paint is missing. A coat or 2 of paint bi-annually would do the trick - and if the splits are unsightly they can be filled and sealed pretty quickly with an epoxy or wood filler.

If this is not a pressure treated post, it shouldn't be in contact with concrete. You can paint and seal it or wrap with something it will not help, any trapped moisture under the paint will deteriorate the post, and by the time paint will start to bubble it will be too late.

If this is a structural post supporting the roof above the last thing you want is take a chance.

That being said, it is very inexpensive to replace this post and most likely by the time you buy the filler and primer, and paint to restore this 4x4...and the amount of money you and time you will spend finishing this post, it will cost less to get a new maintenance free post which you don't have to touch for many years to come. Just saying :-)

GN is correct in this regard. While it's not an emergency, if the base of that post (where it meets the concrete) is not sealed up properly than moisture will eat away at the base via continuous rainwater or snowmelt. Good eye GN.

Thanks guys for your great feedback. The bottom of the post is still descent shape as I'm in CA, not much rain and no snow. But it's very hot during summer.

One concern I have with replacing the post is that I have jack up the porch a bit to put in the new post with bracket. I'm afraid the stuccoed eaves will crack. I always find it very challenging to patch the stucco with the same color.

As usual, we concur completely with GN Builders. If you can have a local engineer look at it firsthand maybe they'll tell you it's fine? In the photo the wood doesn't look like it's rotted...., but more importantly that's a crack not a check! Based solely on the photograph and the fact that it is the only load bearing post.... prudence dictates to just replace it. A 4x4x10' #2 ground contact piece of PT will run you about $13.00 https://www.homedepot.com/p/4-in-x-4-in-x-10-ft-2-Ground-Contact-Pressure-Treated-Timber-288741/301913694

If you want to spend a little more money and upgrade to something that will probably outlast the concrete it is sitting in then............. https://www.soluslumber.com/product/ipe-4x4/