You can run your posting campaign manually. And no matter if the campaign is active or paused.

Use Test Post option for this.

Find the Test Post option in the campaign's log pop-up:

Test Post option is also available in the campaign's editor in the Automation section:

As soon as you run Test Post option, you will see a "Test post is processing.." message. It may take several seconds to make a post. As soon as test post is done a new record will appear in the campaign's log.

Note: Test Post option doesn't affect campaign's posting automation settings.